I don't know what your skill level is but since you're just buying tools & not sure what you need, I'd say not very high. I did body & fender repair, for the better part of 20 years. Autobody is an art form compared to mechanical work. You might look into taking an autobody class, at a local community collage or trade school. You will learn about the tools, you will want, there. I took a year of school, before I got my 1st job. The learning curve, when I went to work, was vertical. It took a few years, before I was really good at it.
For tools, you will need an assortment of body hammers & dollies, an acetylene torch, a mig welder, and an assortment of of sanding blocks & long sanding boards. Wreches, ratches, sockets, & screwdriver. As for air tools, a small angle grinder with a mandrel to fit the 3" 3M roloc disks, a large grinder (9"), long sander, jitterbug, & da.
Good Luck,
Jeff