Check out your local flea market. A couple of months ago I scored an unbuilt 69 Camaro for a dollar and it had an unopened 2 pack of glue inside. Most people at the flea markets buy storage units and only care about the high dollar items. Models can be had for a few dollars and even less if you make a package deal. A fun way to spend the weekend and you would be amazed at the things you find if you take your time and dig around. Also check out any car swap meets in your area. The kits are out there, you just have to be willing to dig around sometimes.