First car with special situation: MINI with special discount or polo?

Hello together, the question has already been discussed several times and I know that many say that Mini= driving fun and Polo= reason. Now I have the following situation:I drive already more frequently car (family, DriveNow, etc.), but for the first time buy my own with insurance in my name (start so above…). Therefore I wanted to buy a used Polo o.Ä. at first and then after 3 or 4 years something from the premium class. “problem” at the decision: I get on BMW u.A. nd / or MINI about family members 25 – 28% discount on new cars. If I would now take a used polo from the dealer with warranty and under 60k kilometers, I pay about 12 – 15k and there is not really much inside. With a new MINI (One petroler) I pay with some extras maybe 20k. What would you guess? Does a MINI pay with 28% discount? Or is the value loss still too high? I drive 80% city by the way. I plan the “first own” car also not 10 years ago If the insurance will be cheaper, I’ll be happy to take advantage of something nicer. Thank you!