Automan_Empire - 7:35 pm on May 31, 2005 (gmt 0)

Don't assume that every blue-collar worker is wowed by a case of beer- some of us are teetotallers, or non-drinking hippies anyway.

I like the letter of referral and the $100-to-10% tip idea. Also, get his business card, and call him for smaller jobs so he can earn all the money, instead of the General who sounds to be in the way.
If he doesn't have a business card, get his name and number, and on top of the bonus today, surprise him in a few days with a box of cards. You may set him on the path of becoming the contractor.