Usually when u get used bikes if you do not know a single thing about mechanic you are toasted because the lbs will milk you sort of speak. The only way to go for sure if you dont know mechanic is with used stuff that is 100000% ok.

Anyhow, what do you mean with bent wheels? Maybe the wheels need to be trued. If thats the case u don't need new wheels but will be cheaper if you have a friend or find somebody at CL to true them for you for free. Stuff i have done a few times already. If the wheels are not true and in bad shape usually the LBS plan is "hey, u need new wheels."

How bad are the wheels? for me a bend rim is a rim bent like an 8 or squared in one part of the rim. If the wheel waves left and right might need to be trued.

Good luck