What year is the car?
If it's an N47, I'd fix it if it were my; otherwise, the engine has to be removed. Because the rockers on the n47 are sacrificial, a new chain kit and some rockers will usually solve the problem. The cam carrier may sometimes shatter; I've seen this happen once.
The engine is removed using a hoist through the top; the most difficult aspect is getting to the top bell housing bolts. On an E90 engine, I can work alone for an hour and a half on the trip.