Fair labour hours for small-medium accident repair? on 2004 Toyota RAV4

I recently received the bill for an accident we caused (rear-ended the car in front of us at about 10-20km/h); it was relatively minor, with the 2011 Accord boot we hit being crumpled several inches fairly evenly across its length - it's hard to describe more accurately. we didn't have insurance at the time, so we're paying the $5600 out of our pockets. I was looking at the detailed invoice for a price breakdown, and noticed that labour was counted at 90 hours' worth. That's two full-time weeks' work for a crumpled rear end. is this a fair labour amount for that kind of work? I'm not in the industry, so I have no idea what is normal. If anyone has any knowledge or thought, it'd be much appreciated!

Asked by for the 2004 Toyota RAV4
this needs to be looked at b4 you can give an est, there could be underlying damage