Cheap parts fitted on my BMW

I purchased a 2012 BMW 120d coupe from a Bidvest Mc Carthy preowned group in Midrand on 29 August 2015, it has been the worse car deal I have ever did in my life. They have been so unprofessional in conducting and finalising the deal. Firstly they sell me a vehicle that has unroadworthy front tyres only after taking vehicle for wheel alignment it was brought to my attention.Secondly the vehicle hasn't had a major service done as per its FSH. After about 21 days the wheel bearings became noisey and the dealership agree to change the tyres and wheel bearings , thinking in my head that it will be changed at a BMW. When finalising the deal I had had been promised by the sales man that the vehicles service parts are being purchased from BMW but it was a lie only after requesting the invoice which had taken me over 1.5 months to get and what is more frustrating is the service parts had been purchased from a local Midas spare shop and not BMW , which BMW does not approve. Upon going to bmw to try and reinstate the motor plan they require the car to have BMW approved products in it. Also after market extendend warranty refused to cover until BMW approved parts be fitted on.