Vet the license. Don't assume the license number your potential contractor supplies is legit, says Steven Smitson, executive director of the commission. The state is seeing more contractors operating without licenses, and some of them are offering fictitious numbers or ones belonging to other contractors.

He advises that you look up the license number HERE or ask about it by calling the commission at 410-230-6309. If the names don't match or you have any doubt that it's the same person, call the company listed with the license information and ask to speak to your guy. One homeowner did that recently, Smitson said, and was told, "He doesn't work here."

Find out about the contractor's complaint history. Call the commission for information.

Don't judge a contractor by his or her advertising. That might sound like a no-brainer, but Smitson notes that it's cheap and easy nowadays to create the appearance of respectability with a website, snazzy business cards and slick handouts. Beware of companies advertising that they are "licensed and bonded" without noting the license number, he says. The law requires that those numbers appear on the ads.

Ask for references. Give the former customers a call to find out how satisfied they were and whether the contractor delivered on the agreed-upon price, deadline and other terms. Better yet: Visit them to check out the work yourself. "It's almost like test-driving a car before you buy it if you can actually go and look at a job," Smitson says. He cautions against relying heavily on websites that offer referrals because some don't check license status or complaint histories.

Seek out competing bids. "It's always a good idea to get at least three," Smitson says. Get everything in writing. He notes that the lowest bid isn't necessarily the cheapest, if it will mean substandard work that will have to be fixed later.

Don't pay too much upfront. "By law, contractors can only request one-third of the contract price as a deposit, and that's once the contract is signed," Smitson says. Anyone who asks for more to cover material costs might have financial problems, he adds. 

What if you get cold feet immediately after you've signed a contract? Homeowners have three business days to cancel without obligation if they negotiated it at their home, thanks to the state's door-to-door sales act, Smitson says.

As for fraud or shoddy work, you can complain to the home improvement commission. If he or she is licensed, you can also file a claim with the home improvement guaranty fund, which covers homeowners' losses of up to $15,000 per contract. (There's a cap of $100,000 per contractor, so you could end up with less if you're one of a long line of claimants.)

Over and above that fund, the state has recovered more than $1 million for homeowners through restitution payments and settlements since July, Smitson says.

Have other tips for cutting down on home improvement headaches? Chime in.