Golf bought – warranty / warranty. 2 problems

Hello. The following problem: I bought a VW Golf 3 Cabrio Bj. 96 on Wednesday from a car dealership (no VW car dealership). With 1 year warranty and an additional 1 year warranty on a house guarantee from the company. I already complained at the test drive that the temperature did not rise to 90 degrees. This should then be fixed. When I picked up the car then, and drove home, the temperature was still at 70 degrees and did not rise any further. itag at VW was here in the village, they found that the thermostat is defective. VW contacted the car dealership and told it and the car dealership takes over 120€ and the rest would have to pay ic hselber (about 30€). Is that OK? Should I accept it that way? I think it is naughty that they are now doing so. Or does the guarantee for it jump in? 2. Problem: The ABS lamp no longer works out. Warranty case or warranty from the car dealership? Thanks already for A few tips!