>>15919719
Keep in mind the Arena has 50 levels, that all have 10 parts. Unless you really like grinding, don't burn yourself out on doing all of it. Do the first 3 parts of each level so you can advance to the higher levels as they become available.
You can find guns, so I wouldn't bother buying too many of them, but if you do, I find scratch damage and HP breakage are the most important.
Besides, you need to save that money for what's really important. Skirts