Happy to chat with you re engine and running gear issues as I have an M6 which has had a bit of work done on it (mostly by myself.) so I have good idea of the pitfalls, maintenance requirements, spares prices etc. Good luck with finding one as there were only 180 odd RH drive M5's made. I looked at 1 prior to purchasing the M6 - it was a shed and the guy wanted £7k. Munich legends may have one at about £13k but I have had no joy from these jokers in the past.

Recent adverts have varied from 5-10k depending on mileage mostly. Autotrader.co.uk is probably the best place or Total BMW magazine.

Look out for timing chain change at £100k - not essential but well worth it if you want to rev it to it's limit. cost me £1300 all in for everything. I have bills for £14k from 1990 on my 154k M6 (it had done 77k in 1990)

Body parts are much cheaper for the 5 than the 6. I am currently enquiring on drivers front wing at £400 plus VAT!

Things I have done

Timing Chain
New headlamp wipers
Total fluid change
Plugs
3 HT leads repaired
New radiator
Intake air bleed valves clean out and synchronisation of throttle plates - helps idle speed and pick up from idle tremendously.
4*240/45/415 TRX tyres at £100 plus VAT each (H rated)
New foglamps
S/H rear light cluster - FAB mail order are usually good and helpful
S/H wash pump
New carpet set (Motormec)
De-chromed - about 3 weekends work - looks great as my chrome was beginning to decay
New hoses
Reset idle control valve
New rotor
Adjusted steering box
New jets for headlamp wash sytem

Things to do
Control arms due to front end shimmy - £78 for 2 arms from Eurocarparts
Maybe a Camshaft swap if I can get some cheap enough (BM want £450 each!)
Rebuild one caliper and replace front discs.
Air conditioning - change out for R134 - big job but I should be able to get seals from a friend
Front wing
Re-underseal underneath - after winter
Track day hopefully next year

Best of luck

email me if you wish and I will provide you witha telephone number

Ian

Are there any M5 owners online? If so, please get in touch, I would really appreciate some direction in purchasing a car -- I'm based in the London area.