New BMW Driver Looking for good car

Howdy, I'm not sure this is in the right place so let me know, but I am a fairly new driver as far as BMW's go, I can handle really any kind of performance (I farm so I drive alot of clunkers) and I'm looking for preferrably an older (used) BMW, but I don't want to break the bank (20,000 max) and it must be automatic. Mind you I can drive manual, but In my everyday car, I don't want to be shifting all the time.
So here's my question:
What is a good car for me that fits that criteria. I dont want convertible, and like all others, it will need to go (fast). I'm new to BMW so I have no idea where to start for this kind of thing. (FYI I'm from Washington State if that helps with anything,) (dealers, parts, etc)
Thanks so much everyone. Any questions about anything, just ask