As someone who went down the exact same road you're going down. Don't do it. Just don't do it. You need a lot more than 20-25K to get a proper 335i.
I promise you if you go this route you will be getting a beaten up, multiple times crashed 335i.. with major issues. The probability of this is just way too high for my risk taking.
Been there.. done that. Wouldn't consider it again.