Contractor Scam Warning Signs: 12 Red Flags to Watch
Contractor fraud costs American homeowners billions annually. These scams follow predictable patterns — here's how to recognize them before you become a victim.
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Analyze my bid free →1. Door-to-door solicitation after a storm
Shows up unsolicited after a hail, wind, or storm event. Offers "free inspection." Often out-of-state plates.
Storm chasers flood neighborhoods after disasters, do quick poor work with cheap materials, and leave before problems surface. They may also involve you unknowingly in insurance fraud.
Never hire a contractor who approached you. Find contractors independently through referrals or licensing board.
2. Requesting 50–100% payment before work begins
"I need to order materials." "The price is only good if you pay today." Large deposit required before any work starts.
This is the most common setup for deposit theft. Once they have full payment, your leverage is gone.
Never pay more than 20–30% upfront. Legitimate contractors do not need full payment to start a job.
3. Cannot produce a verifiable license
Provides a license number that does not match state records, gives a license from a different state, or claims "license not required for this type of work" when it is.
Unlicensed contractors have no accountability — no licensing board to complain to, no bond, no recourse.
Verify every contractor's license at your state licensing board online before any conversation about price.
4. No certificate of insurance — or fake one
Contractor says they are insured but cannot produce a certificate of insurance (COI) or provides one that is expired or shows a different company name.
If an uninsured worker is injured on your property, you may be liable. If their work causes damage, you have no recourse.
Get the actual COI. Call the insurance carrier at the phone number on the certificate (not one the contractor gives you) to verify it is active.
5. Pressure to sign immediately or "lose the price"
"This price is only valid today." "I have another job starting next week." "If you don't sign now, I can't fit you in."
High-pressure urgency is a hallmark of scam operations. It prevents you from getting competing bids or doing due diligence.
Any legitimate contractor will hold a bid for 7–14 days. Walk away from anyone who will not.
6. Cash only — no checks, no cards
Insists on cash payment. May offer a "cash discount."
Cash eliminates your paper trail, dispute rights, and any recourse. Credit cards have chargeback rights. Checks create a paper trail.
Pay by credit card when possible (dispute rights), check as second choice. Never cash.
7. No written contract — verbal agreement only
Contractor says "We don't need all that paperwork, I'll take care of you." or is reluctant to put specifics in writing.
A verbal contract is nearly impossible to enforce. Everything changes when disputes arise.
Never start a project over $500 without a signed written contract specifying scope, materials, price, and timeline.
8. Bait-and-switch: low bid, then change orders
Wins job with an unusually low bid, then finds reasons for change orders that bring the total to or above competitors' original bids.
The low bid was designed to win the job, not to do the work profitably. The contractor always planned to recover margin through change orders.
Require an itemized bid. Compare line-by-line, not just totals. Low bids that omit scope items are not low bids.
9. Material substitution
Bills for Trex Transcend, installs Trex Enhance. Bills for 3,000 PSI concrete, pours 2,500 PSI. Bills for ice shield, installs felt. Nearly always invisible after the fact.
Material substitution is one of the most profitable scams because it is almost never discovered.
Be present during material delivery. Photograph packaging. Know the specific product specs and verify them on delivery.
10. Skipping required permits
"We don't need a permit for this." "The permit takes too long, let's skip it." Especially common post-storm for roofing.
Unpermitted work creates problems at home sale, may void your homeowner's insurance, and means no inspection of the work quality.
If a permit is required, the contractor must pull it. This is non-negotiable.
11. Ghost contractor — subs everything out with no oversight
Contractor you hired never appears on site. Work is done by unknown subcontractors with no management oversight.
You have no relationship with the actual workers, no quality oversight, and responsibility is unclear when problems arise.
Ask who specifically will be on site and who manages day-to-day quality. Visit the site regularly.
12. Suspiciously low estimate with vague scope
Estimate is 30–40% below all other bids. Scope description is very general. Contractor is eager to start quickly.
Either they plan to use inferior materials, plan to change order to the real price, or they will not be able to complete the work and will disappear.
Ask the low bidder to itemize exactly what materials they are using. Compare line by line. Then decide.
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