" I have been a long time BMW enthusiast, despite really having much ownership experience with the brand. I owned a Z3 for a few months, but I recently had to get rid of it for financial reasons (couldn't insure two cars, needed rent money). I currently own a 2004 bone stock v6 mustang (slow as fuck

) This week I am starting a job as a car salesman for a very high volume dealership and have the potential to earn more money than I ever have. My living expenses are low and I plan to keep it that way. I have always been one to jump into the deep end when it comes to projects, however this will be on a whole different level.
The proposition: E30 3 series engine swap with something new. I was originally thinking an N54 but that may be out of my price range considering I would pretty much need a doner car to make it work, since there (to my knowledge) isn't a standalone ecu alternative. I would prefer to do something that is either very rare or has not been done at all (hence the N54 idea). The e30 has always been one of my favorite BMW body styles to date so I plan to stick with that platform.
List of potential engines, in order of preference:
N54 (likely wont happen unless I turn out to be a car selling machine)
S62 (probably also too expensive)
S38
S54 (most likely route)
M52/4 turbo IF I end up not making the money I plan to "