Mobile Rv tech-warranty work-do you guys tip????

Agree that he's doing the job he's paid to do and his drive time is covered. If he seems to care about what he's doing, goes an extra mile to make sure you're happy, is pleasant, I think a $20 would be a nice gesture. BTW, you may want to call on him for something later - maybe a small side job - and that little bit extra could pay off down the road. In any event, if you feel good about his service and attitude, I would tip....and a cool drink along the way is always good.