New car ideas

I am in the midst of buying a BMW. My plan is to sell my car and bike that I have now, which will get me around 14000$ canadian, and want to buy a BMW that would be good for real-estate, as I am switching careers right away here. Since I dont know all that much about BMW's what kind of car should I be looking at, and what are some things I should watch out for when buying a used bmw? Thanks for the help.

Jay