Buy – don’t buy? Please help.

Hello, I drove an Omega 2.2 ED (9/2001, 29.500 km) sample. I liked the car very much and I would like to buy it. I still have a few questions to the Omega experts: 1. At 40-50 kmh you can hear “beat noise” (BUUBBUUBBUUB) from the tires, but the steering remains calm. Did the tires flatten and iron? The car is definitely standing at the dealer’s for a few months. Does a balanced tire help? Or is it possibly due to the brakes? 2. With very slow Fa The dealer said that this was normal with 235/45 R17 tyres with a rough profile. Is that true? 3. The steering wheel squeaks during steering movements until the stop. “Only” a processing error (leather squeaks)? 4. The car still has a factory warranty until 9/2003. Can we extend the warranty? Thank you in advance. Hopefully I don’t hear anything bad from you, I absolutely want to have the car. Xilef