Have you contacted and escalated to Hertz corporate about these issues?

The first one should've never happened - was an easy customer service recovery to have the car come from the airport instead of the Hertz local place you were trying to rent from.

Second one they're supposed to give you a formal itemized quote for repairs, which I find impossible to happen so quickly as well... especially if they're talking about paint and being out of service for rental use. That is supposed to be actual cost, not estimate. Again, escelate to Hertz corporate. Customer care directors are listed here:
https://www.elliott.org/company-contacts/hertz/