Some mug has pushed my rear bumper in and out at some point and all the paint is cracked and slowly flaking off!!

The bumper is in perfect condition just the paint work has taken a battering!
Any one got any ideas on sprayer costs as I haven't got a clue what to expect? I've got a quote from one bloke who wanted £350!!
Is this right? I feel I could get a new bumper already sprayed from the stealers for that!