Sean Leon ST Cupra 300 Leasing or purchase

Hello, I am currently thinking of buying or leasing a Leon ST Cupra 300 4-Drive. I have already received an offer for the leasing: 341€/month with a leasing period of 24 months and annual driving performance of 15000km. However, the transfer costs of 890€ are included in the 341€, i.e. these would not be included in the lease. It would be a new car with almost full equipment, but without a Pano roof. Alternatively, the Seat dealer would have a find another one year old demonstration car with 6000km for 3150€ at the moment. This one would have the Pano roof. If the dealer still comes in the price I actually tend to this car. Which offer price would be realistic here in your opinion? I wouldn’t want to drive the car much longer than 2-3 years. What do you think is the better model, lease or buy in this case?