Vetting and Interviewing Subcontractors
Finding potential subcontractors is step one. Vetting them thoroughly before you hire is step two, and it's arguably more important. This is where you catch problems before they cost you money.
Poor vetting leads to unlicensed contractors, uninsured workers, inexperienced subs, and problem contractors who seemed fine until you hired them. Thorough vetting catches these issues early and saves you thousands in delays, rework, and legal problems.
How to vet subcontractors like a professional GC — what questions to ask, what documents to verify, and what red flags to watch for.
Why Vetting Matters
Catching a problem before you hire costs nothing. Catching it after you've hired can cost tens of thousands of dollars and weeks of delay.
The cost of poor vetting:
| What went wrong | Result | Cost |
|---|---|---|
| Hired unlicensed electrician | Work failed inspection, torn out and redone with licensed contractor | $8,500 + 3-week delay |
| Didn't verify insurance | Worker injured on site, homeowner sued | $47,000 settlement |
| Skipped reference checks | Contractor abandoned job halfway | $12,000 to fix incomplete work + 6-week delay |
| Didn't check past work | Quality was poor, failed inspection | $6,200 in corrections |
The benefit of thorough vetting:
- Catch problems before hiring (zero cost)
- Work with reliable, quality contractors
- Pass inspections first try
- Stay on schedule and budget
- Peace of mind throughout the project
Time investment: 3-5 hours per contractor to vet properly
ROI: Saves thousands in prevented problems
The Complete Vetting Process
Follow this systematic approach for every subcontractor:
Phase 1: License Verification (Non-Negotiable)
Unlicensed work can void permits, will get red-tagged by the inspector, leaves you with no legal recourse, may not be covered by insurance, and violates building codes in most jurisdictions.
How to verify — three steps:
| Step | What to do | What to confirm |
|---|---|---|
| 1. Get the license number | Ask the contractor directly — they should provide it immediately without hesitation | Exact license number and type |
| 2. Verify with state licensing board | Call or check online | License is current (not expired), type matches the work (electrical, plumbing, GC, etc.), name matches, no disciplinary actions |
| 3. Ask for a copy | Request a photo copy for your records | Some states require posting on the job site |
Where to check (varies by state):
- State contractor licensing board
- State department of labor and industry
- Professional licensing division
- Building department (can often verify)
- Reluctance to provide license number
- "I'm working under someone else's license"
- License is expired
- License type doesn't match work
- Disciplinary actions or complaints
- "I don't need a license for this"
- No license when required
- Expired license
- Multiple disciplinary actions
- Suspended or revoked license
What to know about licensing:
- Requirements vary by state and trade
- Some states license by trade (electrical, plumbing, HVAC)
- Some states have general contractor licenses
- Some jurisdictions have local licensing requirements
- Handyman work typically has exemptions (under $X value)
Exceptions:
- True day labor for unskilled work (demolition, cleanup)
- Specialty trades in states without licensing requirements
- But still verify insurance for everyone
Phase 2: Insurance Verification (Equally Non-Negotiable)
Medical bills can run $50,000-500,000+ and property damage can cost thousands. Your homeowner's insurance may not cover construction. Workers' comp is what protects you when the contractor's own worker is injured — general liability will not.
Required insurance types — both are must-haves, not one-or-the-other:
-
General Liability Insurance
- Minimum: $1,000,000 per occurrence
- Preferred: $2,000,000 per occurrence
- Covers property damage and injuries to third parties
- Protects you from damage to your project or neighboring property
-
Workers' Compensation Insurance
- Just as essential as general liability — do not treat it as optional
- Covers medical costs and lost wages for the contractor's own injured workers
- Some states exempt true sole proprietors with no employees (varies by state — e.g., California and many others) — but the moment a sub brings even one helper, workers' comp is non-negotiable.
GL does NOT cover the contractor's own injured employees — only workers' comp does. If a worker is hurt on your site and the contractor has no workers' comp, you (the homeowner) can be treated as the statutory employer and held liable for their medical bills and lost wages.
Collect a current workers'-comp certificate from every sub.
How to verify — four steps:
| Step | What to do | What to confirm |
|---|---|---|
| 1. Request Certificate of Insurance (COI) | Ask the contractor to have their insurance agent send you a COI directly | Sent from the insurance company or agent — don't accept certificates the contractor created |
| 2. Verify the certificate | Review every field on the COI | Policy holder name matches business name exactly; policy dates are current and cover your timeline; coverage amounts meet minimums ($1M+ general liability); legitimate carrier; agent contact info |
| 3. Check for Additional Insured status | Ask to be listed as additional insured | Costs the contractor nothing, gives extra protection, and makes claims easier |
| 4. Verify with the insurance company | Call the insurance company or agent listed | Policy is active, coverage amounts, and policy holder name |
- Won't provide insurance certificate
- Certificate looks homemade or altered
- Insurance is expired
- Coverage amounts are too low
- Won't add you as additional insured
- "Insurance is too expensive"
- "Don't worry, I'm careful"
- No insurance when required
- Expired insurance
- Refuses to verify insurance
- Certificate appears falsified
Special cases:
- A true sole proprietor with zero employees may be exempt from carrying workers' comp in some states (varies by state) — but if they bring anyone to help, get a current workers'-comp certificate
- Very small jobs may not require insurance (verify with your insurance)
- But when in doubt, require it — both general liability and workers' comp
Phase 3: Reference Checking (Most Skip This - Don't)
References reveal quality, reliability, communication, and how a contractor handles problems. Get a minimum of 3 (preferably 5) recent references from projects within the last 12 months that are similar to yours.
Call Every Reference
Why call vs. email:
- Hear tone of voice and enthusiasm
- Can ask follow-up questions
- Harder to provide fake references
- People are more honest on the phone
When to call:
- Weekday evenings (6-8 PM)
- Weekend mornings (9 AM-12 PM)
- When homeowners are likely home
Questions to ask references:
| # | Question | What it tells you |
|---|---|---|
| 1 | What work did [contractor] do for you? | Verify it matches what they told you; confirm scope and scale |
| 2 | Were they on time for the start date? | Tests reliability — good contractors honor commitments |
| 3 | Did they finish when they said they would? | Most critical question — pay attention to any hesitation |
| 4 | Did the work pass inspection on the first try? | For permitted work only; reveals quality and code knowledge |
| 5 | How was their communication during the project? | Did they return calls/texts, keep you informed, avoid surprises or hidden costs? |
| 6 | Were there any problems, and how did they handle them? | Everyone has problems — did they own mistakes and make them right? |
| 7 | Was the final cost close to the quote? | Tests honesty and estimating accuracy; consistent underestimating is a red flag |
| 8 | How was the quality of the finished work? | Are they happy, has it held up, any callbacks needed? |
| 9 | Would you hire them again? | Most important question — 'Yes, absolutely' vs. 'Yeah, I guess' |
| 10 | Anything you wish you'd known before hiring them? | Opens up honest feedback and issues not covered above |
What to listen for:
- Enthusiasm vs. lukewarm responses
- Specific examples vs. generic praise
- How quickly they answer (instant "yes" vs. long pause)
- What they don't say (avoiding questions is telling)
- Whether they'd hire again without hesitation
- Can't reach any references (fake numbers)
- References seem coached (too perfect)
- References are all family/friends
- References have no specific memories of project
- Hesitation about hiring again
- "Yeah, they were fine" (not exactly glowing)
- References mention problems that worry you
- Immediate "Absolutely would hire again"
- Specific praise ("They handled X situation perfectly")
- Mentions going above and beyond
- Enthusiastic recommendation
- Offers their contact info for follow-up questions
Ask to Visit Past Projects
Why it's valuable:
- See quality firsthand
- Meet references in person
- Ask questions while looking at work
- Hard to fake
How to request:
"Would it be possible to see one or two of your recent projects? I'd love to see your work quality firsthand."
What to look at:
- Overall quality and attention to detail
- How work has held up over time
- Similar work to what you need
- Finish quality on visible work
Questions to ask homeowner during visit:
- Same as phone reference questions
- Plus: "Anything you see here you'd do differently?"
- "How has this work held up?"
- Refuses to provide access to past work
- Only offers one reference project
- Reference project is much smaller/simpler than yours
- Quality is poor or sloppy
Phase 4: Background Research
Online presence check:
-
Google the business name
- Look for website, social media
- Check Google reviews (but with skepticism)
- Search "[contractor name] complaints"
- Search "[contractor name] lawsuit"
-
Better Business Bureau (BBB)
- Check for complaints
- Look at complaint resolution
- Rating is less important than how they handle issues
-
Court records (if accessible)
- Search for liens filed by or against contractor
- Check for lawsuit history
- Multiple lawsuits is a red flag
-
State licensing board complaints
- Most boards show complaint history
- Look for patterns
- One complaint may not mean much
- Multiple complaints or serious violations are concerning
What to look for:
- Established business (2+ years)
- Consistent positive feedback
- Professional online presence
- Complaints handled professionally
- No major legal issues
- No online presence at all (for an established business today?)
- Multiple negative reviews with similar complaints
- Defensive or aggressive responses to criticism
- Recent name changes (hiding past problems?)
- Multiple mechanics liens
- Unresolved complaints
Phase 5: The Interview
Phone call first, then in-person if they pass. Meet at your project site (preferred), their office/shop, or a coffee shop — not your home (professional boundary). Plan 30-60 minutes, and bring your plans and specs, list of questions, a notebook, and your project timeline. Include your spouse/partner and anyone else involved in decisions.
Questions to Ask in Interview
About their business:
| # | Question | What you're looking for |
|---|---|---|
| 1 | How long have you been in business? | 2+ years minimum; established is better for new construction |
| 2 | What percentage of your work is new construction vs. remodeling? | Make sure they're experienced in new construction — different codes and processes |
| 3 | How many projects do you typically have going at once? | Too many = you won't get attention; too few = may be struggling; 2-5 active is normal |
| 4 | Who will actually be doing the work? | The person you're talking to, employees, or subs? Will you meet them before hiring? |
| 5 | Do you have experience working with owner-builders? | Some prefer not to — better to know upfront; ask about special requirements |
About the project:
| # | Question | What you're looking for |
|---|---|---|
| 6 | Have you done similar projects in the past year? | Ask for specifics — should mention 2-3 easily |
| 7 | Do you see any challenges with my project? | Tests problem-solving, shows they reviewed your plans, identifies issues early |
| 8 | What's your typical timeline for a project like this? | Compare to your expectations; too fast may be unrealistic; ask what factors affect it |
| 9 | How do you handle code inspections? | Should build to code, know the inspection schedule, and have a good pass rate |
| 10 | What's your inspection pass rate? | Great: 90-100% first-time pass; good: 80-90%; concerning: below 80% |
About process and communication:
| # | Question | What you're looking for |
|---|---|---|
| 11 | How do you prefer to communicate during the project? | Phone, text, email? How often? Will they provide updates? |
| 12 | What do you need from me to do your job well? | Shows they've thought about working with you and sets up success |
| 13 | How do you handle changes or unforeseen issues? | Process for documenting and pricing changes, and communication about problems |
| 14 | What's your warranty/callback policy? | Will they fix issues after completion? What's covered, for how long, and how to reach them? |
About scheduling and payment:
| # | Question | What you're looking for |
|---|---|---|
| 15 | When would you be able to start? | Compare to your timeline; too immediate is a red flag; should book 4-12 weeks out |
| 16 | How long would this project take from start to finish? | Get a specific timeline; ask about factors that could delay; understand dependencies |
| 17 | What's your payment structure? | Should be progress-based; final payment after completion and inspection |
| 18 | Do you require a deposit, and how much? | 10-20% is a common market norm — but your state may cap it much lower (see below) |
A deposit of 10-20% is a common market norm, but your state may cap it much lower. Several states legally cap residential deposits — California and Nevada at the lesser of 10% or $1,000, and Maryland/Massachusetts/Pennsylvania at one-third — and progress payments generally can't exceed the value of work performed. Check your state before agreeing to any deposit.
30%+ is a red flag (and likely illegal in a capped state). 50%+ is a major red flag.
About materials and methods:
| # | Question | What you're looking for |
|---|---|---|
| 19 | Do you provide materials, or do I purchase them? | Varies by contractor; understand who's responsible; affects payment structure |
| 20 | What brands/products do you typically use? | Shows quality standards; lets you research products and discuss preferences |
| 21 | How do you handle site cleanup? | Daily cleanup? Who provides the dumpster? Is final cleanup included? |
About problems (important):
| # | Question | What you're looking for |
|---|---|---|
| 22 | Tell me about a project that didn't go as planned. What happened and how did you handle it? | Everyone has problem projects; what matters is how they handled it; refusal to discuss is a red flag |
| 23 | What happens if I'm not satisfied with the work? | How they handle complaints, willingness to make things right, and their dispute-resolution process |
What to Observe During Interview
Body language and demeanor:
- Confident but not arrogant
- Makes eye contact
- Listens more than talks
- Asks YOU questions too
- Takes notes
- Professional appearance
How they discuss your project:
- Shows genuine interest
- Asks clarifying questions
- Points out potential issues (good)
- Doesn't promise perfection
- Realistic about timeline and challenges
- Speaks negatively about other contractors or clients
- Promises everything will be perfect
- Dismisses your concerns
- Doesn't ask questions about your project
- Seems distracted or disinterested
- Pushes for immediate commitment
- Bad-mouths building inspectors
- Suggests cutting corners or "inspector won't see that"
- Asks thoughtful questions about your plans
- Suggests improvements or alternatives
- Discusses code requirements
- Explains their process clearly
- Sets realistic expectations
- Demonstrates expertise through specific examples
- Speaks respectfully about inspectors and process
Phase 6: Site Visit (If Possible)
Visit an active job site (with permission). What to look for:
- Organization: Clean, organized, materials protected
- Safety: Proper safety equipment, safe practices
- Quality: Work quality on visible elements
- Crew: Size of crew, professional behavior
- Equipment: Professional tools and equipment
- Communication: How foreman communicates with you
- Messy, disorganized
- Safety violations
- Unprofessional behavior
- Poor quality visible work
- Minimal or no equipment
- Clean and organized
- Safety practices evident
- Quality work visible
- Professional crew
- Proper equipment
- Respectful interaction
The Decision Matrix
Rate each contractor on these factors (1-5, with 5 being best):
| Factor | Weight | Contractor A | Contractor B | Contractor C |
|---|---|---|---|---|
| License verified | Must have | Pass/Fail | Pass/Fail | Pass/Fail |
| Insurance verified | Must have | Pass/Fail | Pass/Fail | Pass/Fail |
| References | High | 4 | 5 | 3 |
| Experience | High | 5 | 4 | 4 |
| Communication | High | 4 | 5 | 3 |
| Price | Medium | 3 | 4 | 5 |
| Availability | Medium | 5 | 3 | 4 |
| Professional demeanor | Medium | 4 | 5 | 3 |
| Code knowledge | High | 5 | 5 | 3 |
| **Total** | **30** | **31** | **25** |
Must-haves (pass/fail):
- Valid license (if required)
- Current insurance
- Checkable references
If they fail any must-have, eliminate them regardless of other factors.
Weighting:
- License/Insurance: Pass/fail only
- High importance: References, Experience, Communication, Code knowledge
- Medium importance: Price, Availability, Professional demeanor
- Lower importance: Personality, location, company size
Making the decision:
- Eliminate any that fail must-haves
- Compare total scores
- Price shouldn't be the deciding factor
- Trust your gut if something feels off
Common Vetting Mistakes
| Mistake | Why people do it | The cost | How to avoid |
|---|---|---|---|
| 1. Skipping license verification — taking their word for it | Seems awkward, takes time, trust the person | Unlicensed work fails inspection, must tear out and redo | Make it standard practice, verify every contractor |
| 2. Not calling references — reading online reviews instead | Calling feels awkward, online reviews seem sufficient | Miss red flags that references would have revealed | Call at least 3 references, every time |
| 3. Accepting homemade insurance certificates | Seems official, easier than verifying | Certificate is fake, you have no coverage, liable for injuries | Require COI sent directly from insurance company or agent |
| 4. Hiring based on price alone — choosing the lowest bid | Budget pressure, want to save money | Low bidders often create expensive problems | Vet thoroughly regardless of price, eliminate extreme high and low bids |
| 5. Not meeting in person — phone and email only | Saves time, seems efficient | Miss important red flags visible only in person | Always meet finalists in person before hiring |
| 6. Ignoring your gut — hiring despite bad vibes | Can't articulate the concern, seems irrational | The concern was usually valid | Trust your instincts, there are other contractors |
Vetting Checklist
Use this for every subcontractor:
License Verification
Insurance Verification
Reference Checking
Background Research
Interview
Final Decision
Red Flags Summary
- No license when required
- No or expired insurance
- Won't provide verifiable references
- Can't verify business exists
- Major safety violations observed
- Multiple lawsuits or liens
- Demands large upfront payment (50%+)
- Suggests cutting corners or avoiding inspections
- Your gut says no
- Relatively new business (under 2 years)
- Limited experience with your project type
- Some negative reviews (check how they responded)
- Pricing significantly different from others
- Availability seems too immediate
- Mixed reference feedback
Questions to Ask Yourself
Before hiring any contractor:
- Did they pass all must-have requirements (license, insurance, references)?
- Do I feel confident in their ability to do quality work?
- Do I trust they'll show up and finish?
- Am I comfortable with how they communicate?
- Is their price fair (not necessarily lowest)?
- Does my gut tell me this is the right contractor?
If you answer "no" to any of these, keep looking.
Next Steps
Once you've thoroughly vetted your contractors:
-
Get Quotes → - Request detailed quotes from your top 2-3 vetted contractors
-
Create Contracts → - Protect yourself with proper written agreements
-
Payment Structure → - Understand when and how to pay
**Remember