If I were rich I'd buy a brand new X5M and let the dealer worry about the issues.
You worried me
I actually heard good things about it. I was told if the car survived to 40-50K miles most likely the major issues were solved.

Bellow are few decent cars(speaking without actually having checked any of these cars). If I was to buy I will do a full PPI at the closest BMW dealer.

https://www.autotrader.com/cars-for-...modelCode1=X5M

https://www.autotrader.com/cars-for-...modelCode1=X5M

https://www.autotrader.com/cars-for-...modelCode1=X5M

https://www.autotrader.com/cars-for-...modelCode1=X5M

https://www.rochellasauto.com/2012_B...Y_19090768.veh

https://www.uabcars.com/detail-2013-...-17054736.html

https://www.autotrader.com/cars-for-...modelCode1=X5M

https://www.carsforsale.com/vehicle/details/43728605

https://www.carsforsale.com/vehicle/details/42424691