Often all it takes for a DIYer to get 10 to 20 percent off supplies, including lighting and draperies, is a simple request for a trade discount. Typically reserved for contractors and designers with credentials, such as a professional license or a resale tax ID number, it's often extended to valued customers. Or if you've worked with a pro before, ask if you can use his business information. "I have clients with small painting projects that they want to do on their own, and I tell them to use my name at the local paint store, and the clerk will give them my discount," says Siegrist. "It's a goodwill gesture that doesn't cost me a thing."