2007' Audi A4 Avant

I've had the Audi for 3 and a half years. I have driven the car for over 80,000 km and it has always performed great. I used it for commuting to work and studying, a route of about 30-70 km.
Last year, Audi replaced:
-camshaft
-camshaft bearings
-complete timing
-oils and filters
-valve cover
-injector wiring harness
-head gasket
-the head has been regenerated
-oil cooler
Since then, the car has covered about 15,000 km. Additionally, the turbine was replaced about 45,000 km ago. Front pads replaced last year. I have papers for all repairs.
What needs to be done is that the thermostat started to fail a few days ago and the Audi sometimes only heats up to 70 degrees while driving.
Apart from that, just get in and go
The photos show that the Audi has a dent on the driver's door and rust on the front fender on the passenger side.
Fees until July/August