Good advise there. Check out both of these issues very carefully.Any work on the oil filter housing is going to be big $$$ because it's located at the back of the engine instead of the front as found on previous iterations of the BMW I6. VANOS solenoids are also on the back.
I had the vanos system rebuilt on (literally) the last day of the warranty. The dealer didn't know how to diagnose it so I took them the information. Got the diagnostic information from Bimmer Roadfly. On my 528i the diagnosis was made by observing "porposing" at idle when cold. I had to leave the car at the dealership overnight so it would be cold enough to demonstrate the problem. I hate to think what that repair would have cost (a couple of thousand I expect).
And my oil filter housing was weeping. I suspect most of them do. It sounds like an innocuous enough problem (replace a $10 gasket) but it would have cost several hundred bucks to replace it. And that assumes none of the plastic stuff they have to take off to get at it broke. And the housing was on the front of my engine.