Big job or small, whether you're hiring outside help for repairs, upgrades, or a total gut job, roll up your shirtsleeves for a bit of pre-renovation prep.
Find a pro in the know
Word-of-mouth is a great place to start. There are online services that offer referrals and ratings, too. If Consumers' Checkbook or Angie's List cover your locale, start there. Providers cannot pay to be listed on these services (on Angie's List, ratings are augmented by members as well as staff). Pros can pay to be listed on ImproveNet.com and ServiceMagic.com, which work more like referral services, with customer reviews on completed jobs. And Contractors.com designates providers that are certified by the company and adhere to its code of ethics.
Do a background check
Most states require licenses for plumbers, electricians, contractors, and anyone who does large jobs. Verify with your state licensing board or local building department that your potential hire has a valid license. Search license info at contractors-license.org, and check with the Better Business Bureau at bbb.org.
Get on the same page (literally)
A good (meaning detailed) bid will save you stacks of money on headache medication. Some contractors have been reluctant to give me a written bid unless they were relatively certain I was going to hire them.
The initial bid may be cursory, so before you break drywall, get all the details -- everything from the make, model, and color of appliances to a breakdown for labor and materials to dispute resolution steps and warranty information -- in writing.
Cover your back
Power tools are dangerous. Make sure your contractor has the right insurance coverage (worker's compensation, general liability, automobile), or else you could be liable for workers' oopsies.
Ask for lien waivers that state you are not responsible for supply or labor payments your contractor fails to make. And avoid any language that says your house is collateral for payment.
Pay as you go
Never pay for work in full before the job's done. Typically, contractors will require a down payment (10% of the project price) before the job starts, and around one-third as work begins, a similar amount halfway through, and the final payment upon completion. You may also have to pay for supplies as work progresses. Get receipts.
Brace for changes
Have some play in your budget. Big jobs commonly have cost overruns in the 5% to 15% range. I had a handful of "change orders" -- contractor-speak for "Have your checkbook handy!" -- for unforeseeable things like old wiring that wasn't up to code and last-minute additions (two entryway closets). Get these in writing, too, with the same details as the original contract.
If your job is big, invest in some heavy-duty folders to keep the mountain of paperwork (permits, bills, invoices, cancelled checks, receipts). Schedule regular check-ins, too.
Not all work delays are the contractor's fault. Contractors work best when all the materials they need to complete the job are on hand. Plan ahead if some items you want to use need to be special-ordered. Indecisiveness and delays will cost you, so be quick with decisions.
Discuss with your GC whether you plan to subcontract or do some work yourself. In addition to scheduling issues, there are legal ones. Contractors whose names are on the permit may not want an outsider doing work for which they could be held legally liable.