I'm with Gene!! How much ya got?? As John mentioned, stay local and try to find someone you know. I'm just finishing up a kit for someone that asked me to build for him. I didn't want any money from him, he is a friend and super guy. He put a $100.00 on me anyway for stuff for one of my own planes. That hundred comes out to about 35 cents an hour. In this case the kit was missing a lot of parts I had to make myself. It's just a CG Cub but if I was building for a true customer it would have been $250.00 plus parts and supplies.
For covering jobs I have charged according to the design and plane type. That and the cost of the covering. Get yourself a friend!! When I teach someone to build and cover there is no charge at all except materials like glue and epoxy. After the first time building I will not build a plane for them but will help when they run into problems.
As John mentioned there is plenty of help if you ask around your local clubs.
Gene