Chet's Transmission & Clutch

I haven't had enough time to give a honest review, but with what I have I will say the car I purchased is a BMW 528i. There are a few issues with it but that is expected with used cars. A month later the cars transmission began to slip and got worse. I took in back for them to look at, when I picked my car up they told me nothing was wrong with the transmission. I happen to know one of the head guys a the dealership where I live told me that the transmission was never checked. Also the car just died on me. Long story ,short: I had to replace the Cam Shaft sensor, Crank shaft sensor fuel filter, fuel pump, transmission filter(to add 7 quarts of trans fluid) and now all the window regulators are failing meaning that the windows will not roll down. What do you do? I it used. I was told take your time with the payments. I am donating it to the repairs. I am not sure if Chet's is in the auto sales or repair business, but both could need a little attention.