Is the BMW M3 a good investment?

The thesis

The last naturally aspirated straight-six M3, and widely regarded as the purest expression of BMW's M philosophy. Manual coupes command the highest premiums; SMG cars lag significantly. Quality examples that sold for £10–15k mid-2010s now fetch £20–30k, with exceptional low-mileage cars over £35k. The E46 has definitively escaped the 'minefield phase' where many were modified or neglected. Clean, stock, manual coupes are increasingly rare, and the contrast with turbocharged successors reinforces its collector appeal. Still in mid-cycle: not cheap, but not yet at the stratospheric pricing of the CSL variant (£100k+). The standard M3 offers 90% of the experience for a third of the cost.