Mike Hartman at Foothill Aircraft (Cable Airport) does prop balancing for Foothill Aircraft and on the side when not working for Foothill Aircraft. He has over 25-years experience doing helicopter rotors and props. IF you do all the mechanical work of taking the cowl and spinner on and off plus stand by the airplane waiting to run the engine, he will give you a very good CASH price. He did my prop right after my test phase over 15-years ago. He charged me $100 cash back then. He does not charge much more now if you do the mechanical and are standing by to start between adjustments.