Most people hire a contractor the same way: get a couple of quotes, pick the one that feels right, and hope. That works more often than it doesn't — but when it goes wrong, it goes wrong expensively, and almost always for reasons that were visible before anyone picked up a hammer.
These are the five checks worth doing every single time. Together they take about twenty minutes, and they filter out the overwhelming majority of problems.
1. Confirm the license yourself
Ask for the license number, then look it up. Don't accept a photo of a card and don't take the number on faith — every state runs a free public lookup, and it takes under a minute.
You're checking three things: that the license is active and not expired, that it's in the name of the business quoting you, and that the classification actually covers your job. A general contractor's license doesn't automatically authorize electrical or plumbing work; those are usually separate trades with separate licenses.
If someone gets defensive when you ask for a license number, you already have your answer. Legitimate contractors expect this question.
2. Get the insurance certificate — from the insurer
There are two policies that matter. General liability covers damage to your property. Workers' compensation covers injuries to the crew while they're on your property. If a contractor carries neither and someone gets hurt in your home, you can end up personally exposed.
The right move is to ask the contractor to have their insurance agent send you the certificate directly. It costs the contractor nothing, takes one email, and it means you're looking at a current document rather than a PDF that may be years out of date. Check that the coverage dates cover your project window.
3. Call two references — and ask better questions
Any contractor can hand you three names who will say nice things. The useful part isn't whether the reference is positive; it's the specifics you can only get from someone who lived through the job.
- Did the final price match the estimate? If not, what changed and how was it communicated?
- How did they handle the thing that went wrong? Something always goes wrong.
- Did the same crew show up each day, or did it change constantly?
- How long did the job sit unfinished at the end, if at all?
- Would you hire them again without shopping around?
Ask for a reference from a job finished at least six months ago, not just last week. Problems with workmanship tend to surface after a season of weather.
4. Read the scope of work before the price
Most disputes aren't about money directly — they're about what the money was supposed to buy. A real proposal spells out materials by brand and model where it matters, what's included and what isn't, who pulls the permits, who hauls away debris, and roughly how long the work will take.
A one-line quote with a number at the bottom isn't a proposal. It's a placeholder for an argument later. If two bids are far apart on price, the reason is nearly always in the scope, not in the profit margin — compare what's actually being done before you compare totals.
Permits are a feature, not a hassle. A contractor steering you away from pulling one is usually protecting themselves, not saving you money — unpermitted work can surface as a problem when you sell.
5. Look hard at the payment schedule
A reasonable deposit covers materials and gets you on the schedule. Payments after that should be tied to progress you can see — rough-in complete, drywall up, fixtures set — with a meaningful amount held until the work passes final inspection and you've walked it.
Two patterns deserve real caution: a demand for most of the money up front, and pressure to pay in cash with no written contract. Many states also cap how large a deposit a contractor can collect on residential work, so it's worth knowing your state's limit.
The short version
Verify the license yourself. Get insurance confirmation from the insurer. Call two references and ask what went wrong. Read the scope before the price. Tie payments to visible progress.
None of this is adversarial, and none of it will offend a good contractor. The people who mind these questions are, reliably, the people you were going to have a problem with.