You will quickly find out that all you really need is......
Box of square head screws AND the screwdriver to put them in and out.
Because that is what your RV is put together with! :B
Seriously though I brought 2 of my construction screw guns with and 4 years and counting I have not used them.
My Mobile RV guy had a hand held powered screw driver that "fit in the palm of his hand" that he was using on everything on my MH one day.
I asked him about it. He said all the battery operated screwdrivers where a joke until he found this one. Said it lets him get into all the tight spaces that all RV's seem to have, where a screw gun won't fit.
Craftsman Evolvhttp://www.sears.com/craftsman-evolv-17088-3.6-volt-ni-cd-cordless/p-00917088000PI use THIS tool just about every day on the road! Small but VERY powerful and charge lasts a long time. Find it at Kmart & Sears. They also sell a nice kit of bits to go along with it.......including that square one for those pesky square RV screws! :B