tl;dr
Didn't notice for quite a while since I live in a student area and don't use my car that often. But I noticed the other week that there was a dent on my rear-left wheel arch (pictured).

Was a bit angry, but what can you do? I'm not sure when it occured so I can't really pin it down. I've got bigger things on my plate at the moment, like finals.
Anyway, I asked a repair shop and they said that it'd probably be about £520+VAT to get it repaired. Seems a bit much to me?
What do you guys think?
Also, a very minor dent on my bonnet. But I think that might have been from my neighbours, since my housemates were climbing on their cars a while back for a laugh. (we're friendly with our neighbours). Otherwise, a complete mystery. Probs going to suction cup that bad boy.