I wouldn't trust Carfax on maintenance records being anywhere near accurate. A good owner keeps their service records for when they sell the car. There should be nothing to hide. The reality is every machine built requires maintenance and it should be expected that an 8 year old car will require some non-scheduled maintenance.
I have a 2012 Cayenne S Hybrid with 163k miles. I did all services as per the maintenance schedule in the book at the dealer up until 150k miles.
I did a full brake job at 66k miles even though the dealer said I probably could get another 5-10k miles out of them before the wear sensors would trigger. I did a second full brake job at 160k miles. The hybrid system when driven properly really extends brake life, so your results will likely be different. I would ask if the brakes have been done and would suggest getting a measurement on the pads and rotors. Pads and rotors were about $900/axle.
In terms of non-scheduled maintenance, my car has required the following repairs...
Fuel tank level sending unit and new fuel pump at 120k miles. Those repairs set me back about $2400 I believe.
The oil level sensor required replacement at 160k miles, and cost about $480. There was some corrosion on the connector/wiring from the winter road salt exposure on the bottom of the car (northeast part of the country).
My dealer was charging ~$600 for 10k mile service, and quoted me $3600 for 160k mile service which was the impetus to switch to an independent Porsche service specialist for a significant savings. The only other big service item is the supercharger belt service every 60k miles, but that is specific to the hybrid.
I replaced the original factory battery myself at 150k for a cost of $270. Dealer quoted me $850, but said I could wait another 6 months. Porsche parts quoted $450 for battery. VW quoted same battery type/group for Touareg at $260. Interstate was $235. A set of 12 point star bits to remove the driver seat cost $36 on Amazon. Took me under an hour to remove the driver seat and replace the battery. After 7.5 years and 150k miles and a winter season ahead of me, I was more than happy to replace the battery and not risk getting stuck in the cold.
My car burns a quart of oil about every 4k miles. If I do a long highway drive that sees my oil temp hit 215+ then my oil burn accelerates noticeably.
I'm probably going to need my catalytic converters replaced as I am not getting P0420/P0430 Catalyst Below Efficiency error codes on an increasingly frequent basis. Considering using Touareg cats to cut the repair bill by some $1500.
Anyway, hope that helps. Obviously, every car is its own animal.