How much technical know how you need could be very subjective. If all you want them to do is grease the bearings, fairly stragiht forward. But if the refrigerator quit, or you want the trailer sealed against all possible leaks you may want more "skilled labor". Working on a vehicle you plug into the obd port and it tells you to change the flux capacitor. No such thing on a RV. And chances are, if they'll pay me more to change flux capacitors then to seal up an RV, I'll change flux capacitors all day long.