Historically, thermal imaging cameras have been quite pricey. But this manufacturer has lowered the cost of its FLIR i5 to a more affordable level. The product, which allows contractors to diagnose problems or improve energy efficiency, has a 2.8-inch color display and 80x80 pixel resolution. It produces thermal images that are accurate to within 2 percent. Cost: $1,595. FLIR Systems. 800-464-6372. www.flir.com.