I'm doing this as an almost full-time 'hobby' as well but, I have to draw the line when it comes to traveling 20 miles one way to pick up even a donor or $10 small engine.. That comes to an easy $8-10 in gas plus at least an hour out of my day lost.. If I can schedule multiple pickups in one area, I'll do that. I keep a list of folks that I've talked to and so far they're good with that. I had one guy that was going to trade me a practically new Poulan Pro chainsaw for a donor edger that I picked up and spent some time on it getting it running and looking good.. But, he was an hour away and that's definitely costly when it comes to gas and time used..