Slightly noisy engine - top end

[andye30m3]

well the car I'm looking at went in for it's inspection today.

Went through reasonably well, needs a spring, door seal, air con belt and the boot looking at

only worrying things are a fair amount of play in the diff to the point at which it really needs replacing and the garage (Munich Legends) said that the engine was slightly noisier than others they had in, coming from the top end, especially when cold.

Any idea's what the worse case is for this? I'd have thought they'd picked up on a vanos, didn't seam to be suggesting this was going to cause a definite problem. Are some M3 engines just noisier than others?

Shame as the rest of the car came back fine, with good traceable history, 50k miles, recent inspection 2 and new disc and pads.

In two minds as to what to do, it is good value compared to what other similar cars are being advertised at.