Definitely get a PPI. Then use the full info from it to negotiate price hard.
A Boxster is one of the easiest vehicle to wrench on. That said, and even though it's a 13 almost 14 yo vehicle, many parts are priced like it's a brand new $60k Boxster. FWIW, replacing condensers is easy w/ simple removal of bumper skin.
Good luck but don't be afraid to move on as there are countless nice Boxsters out there for sale.
