Temporary thread hi-jack - I'm about to get another star here!! :lol:
Anyway OP, I think it depends how important it is to you to keep miles down on your Z4 but the M54 engines seem to be pretty good at high mileages and on a 53 plate I can't see it's value plummeting with more miles. On that basis if it does the job I would just put the miles on it and enjoy!
When I bought my first Z4C I knew I would need something else for taking my mother to hospital appointments (she is 94 now) so I found a cheap as chips 323F Mazda from 1996 with just 2 previous owners and 65,000 miles. Cheap road tax, non-interference engine so run until cam-belt snaps, 40 mpg easy - but it was so boring I avoided using it whenever I could!
Man maths inspiration - I bought a 325ti instead so it's always an N/A straight 6 petrol with RWD now! Lovely, but as a result I didn't use the Z4C enough to justify 2 x insurance and 2 x Band K RFL.
Which is why I replied to a post from someone looking for a Coupe and ended up taking a deposit from him - 2 or 3 days later I realised what I had done, so had to go and find a replacement!
I probably should just go and find a 130i, but the Z4 feels so special whenever I use it I plan to use it more - hopefully split use roughly 50/50 with the 325ti. I mean, apart from RFL and insurance I can only put petrol in, or miles on, one at a time! :roll:
If I didn't need to do the elderly transport I would just have the Z4C - so in a roundabout way I'm back to my original thought for the OP I suppose! :?