That ding is worth repairing. It'll be a ton more work fitting a new deck.
Get a scrap fender and a hammer & dolly and practice. Watch a few videos first and get the concept from that. Massaging little guys like that isn't terribly hard. Worst case the body shop will charge you a couple hundred more.
It's not hard to get most of a dent like that out. A body shop could tack the hole shut and finish it off when the time comes.
