Put it in writing before the contractor picks up a tool

Quick answer: Before work starts, get these on paper and signed: exactly what's being done, the price and when you pay it, the dates, how changes get approved, proof of license and insurance, and lien waivers with every payment. Then pay a local attorney an hour to read it.

Say you're redoing the back room of your shop. The contractor quotes $18,000 over a handshake and a text. Three weeks in, he pulls up the old flooring and the subfloor's rotted. "That's extra," he says. You thought "floor" meant the floor. He thought it meant the surface.

Neither of you is lying. Nobody wrote it down. That's the whole genre of contractor disputes.

Write the scope like a stranger has to build from it

"Install new flooring" isn't a scope. It's a hope.

A real scope names the product, the square footage and the rooms. It says what gets torn out, who hauls it away and who covers your inventory while the dust flies. It also lists what's not included. Exclusions feel rude to write. They save more money than anything else on the page.

If you haven't picked materials yet, use an allowance: "$4 per square foot for tile, supplied and installed." Then if you choose the $9 tile, everybody knows the difference is yours. If you choose the $3 one, you get the credit.

Pay for progress, never for promises

Keep the deposit small. Many states cap deposits on certain kinds of work, so check yours. A contractor who needs half the money up front to buy materials can usually set up a supplier account or buy the materials himself and invoice you.

Tie payments to finished stages, not calendar dates. One common shape: a modest amount at signing, three payments as defined stages get done, and the last ten percent held until you've walked the job and the punch list is cleared. Write each stage so that a third party could tell whether it's finished.

Pay by check or transfer. Cash with no receipt is how a paid invoice turns into an unpaid one.

Dates, and what happens when they slip

Put a start date and a completion date in the contract. Without them, your job is the one he does when the other jobs are slow.

Be fair about delays. Weather happens. Suppliers run late. A good clause says which delays count, and that the contractor owes you notice in writing when one hits. If you want a daily credit for late finish, expect a reasonable contractor to ask for the mirror image: extra time when you're the reason, like keys that don't show up or a decision you sit on for a week. That's a fair trade. Take it.

The change-order rule

"While you're in there" is the most expensive phrase in the trades.

Add one sentence: no extra work gets done or billed unless a written change order, with price and added days, is signed first. Text counts only if the contract says text counts. Then follow it yourself. Most of the time the owner breaks this rule first, with a casual "sure, go ahead" on the job site.

Handle the rotted subfloor before it happens. Write a unit price: "Replacement of damaged subfloor, $X per sheet, installed." Now a surprise has a price tag, and nobody has to negotiate in a torn-up room.

Insurance, license and the guy on the ladder

Ask for a certificate of insurance showing general liability and workers' compensation. Have the contractor's insurance agent send it to you directly. A photocopy he hands you proves he once had a policy.

If a helper gets hurt on your property and the contractor has no workers' comp, you could be pulled into it. How far depends on your state and your own coverage, so ask your insurance agent before the job, not after. Where your state licenses the trade, look the license up on the state board's site. It takes five minutes.

One related warning. If the "contractor" works your hours, uses your tools and answers only to you, the label may not hold up. Misclassification is a real exposure, and what to file before your first employee starts covers the other side of that line.

Lien waivers, the clause nobody asks about

In many states, a subcontractor or supplier who doesn't get paid can file a lien against your property, even if you paid the general contractor in full. You can pay twice for the same lumber.

The fix is paperwork. Get a signed lien waiver with each payment, and a final unconditional waiver with the last one. Ask the contractor to list his subs and major suppliers up front. Rules and forms vary by state, which is one more reason to let a local attorney look.

Warranty, cleanup and how it ends

Put the warranty in writing: how long, what it covers and who you call. "He's a good guy, he'll come back" is not a warranty.

Put cleanup in too. Broom-clean at the end of each day, debris gone at the end of the job, your space left cleaner than it was found. Good contractors already work this way. The clause just means the ones who don't have to explain why.

Then write down the exits. How either side can end the contract, how the contractor gets paid for work completed, and what happens to materials already bought. For disputes, require written notice and a window, say seven days, to fix the problem before anyone calls a lawyer. Mediation before a lawsuit costs less than the lawsuit almost every time.

What this is really for

A contract isn't a sign you don't trust the man. It's how two people stay friends through a hard stretch of dust, noise and money.

Good contractors like clear paperwork. It protects their pay and their time, and it keeps customers from inventing scope halfway through. If someone gets offended when you ask for it in writing, you've learned what you needed to know before you paid him a dime.

Hold up your end. Pay when the milestone's met. If you've ever chased a customer for money, you know exactly how he feels waiting on yours, and most late invoices are a process problem on both sides of the table. Know your cash before you sign, too. The weekly numbers that keep a small business out of trouble will tell you whether you can afford an $18,000 detour.

This is general education, not legal advice. Contractor rules differ by state, and some states require specific language in home-improvement contracts. Have a local attorney read yours once before you sign. An hour of his time is cheaper than the second set of floors.