Yeah, there's no way on Earth that's only $500-800 in damage. My car was hit last year (parked on the street, so definitely not my fault) and even though the damage looked fairly minor on a brief glance, it ended up destroying the rear axle and causing frame damage, aka "total loss." This here is probably at least $1,500 and that's assuming the damage is only to the door and the frame around the door is still structurally sound (it's hard to tell from the pictures, but it looks warped).
Zeze, when you say your car is old, how old, and how much is it worth? If the damage is north of 80% of the FMV of the vehicle, they'll probably just total it and you'll need to buy something new. Which is obviously a bummer, but, hey, new car!