[Brian in Tucson]

I would have the oil changed at a local independent german car shop. Have them do an inspection as if you are buying the car. They will tell you what might be wrong and what needs attention to make the trip.

If the tires are more than about 5 years old, it would be a good idea to spring for new ones, even if the current ones look okay. A tire shop can check the dates if you don't know how.

I would spend the bucks and get the car detailed. Much more cost effective than DIY. The earthy smell from the air ducts is concerning, if rodents have been visiting, there may be dried urine and/or poop. Very nasty, and hazardous to your health.

A good 01 Boxster S is worth at least $12 grand. A good low mile one could even be worth more. I would be cost effective to put several grand into this car. Congrats. I'm jealous.