Here's something to keep in mind. A rear end hit on these "newer" 911's can be just a bump, or it can end up being severe frame damage and require extensive repair. You need to request information on the damage and make a judgement call. There is a popular Rennlist thread about rear fender bender damage on a 2013. Here's the thread below, and I'm including pictures from the thread in case it's not reachable. You would have never suspected that a minor visible damage to a bumper cover would end up with $30k in frame repair. Would you consider this car for purchase if you saw the picture of damage from the accident - but no other evidence?
https://rennlist.com/forums/991/760365-so-you-think-it-s-just-a-bumper-job-huh.html
Slight crease in bumper is visible near the plate -

Bumper cover removed - impact bar is damaged and crushed -

Frame damage -

Repair requires engine removal and fixture use -