Do you have an air compressor? To prep a jeep your gonna want one.. After that youll want a orbital sander which can be purchased at harbor frieght for fairly cheap.. Get yourself some sandpaper in grits 80, 180, 320 or 400 and some 600.. Youll also need some scotch brites and some filler/bondo..
Once ya got all that, youll want to start by fixing any damaged areas, and your deep scratches.. Use the 80 grit to sand those damaged areas only if your using filler on it.. You dont want to sand the scratches all out.. Instead, sand the ares with the 80 grit and use filler to fill the scratches or else you will have low spots in the final finish.. Sand the filler with 180 or any areas that filler isnt used but there is some chips or lighter scratches..
The rest of the body needs to be sanded with the 400 grit paper and needs to sanded to the point to where there is no shine in the paint.. Get it all good cuz prep is key to an overall good paint job... Anywhere your sander cant reach you need to use red scotch brite and scuff those areas..
Once all that is done go back to your repair areas and primer (rattle can primer is fine but if you have bare metal showing get a self etching primer) and prime all those area covering all the 180 grit sandpaper marks.. Once its all dry go back and sand those primer spots with some 400 grit paper and that should get you close to being painted.. I like to do a quick once over with some 600 grit paper just to make sure sand scratches dont show through the new paint job.. Once your to that point im sure the paint shop can handle the rest and save yourself some greenbacks.. It can be done as my xj is now rescue green.. Did it all myself start to finish..