Frazzie - welcome to the Forum. Lots of advice on her about purchasing a Zed. There is a pre purchase checklist link in my signature which may help when you are looking.
Your budget is OK and certainly should see you get a 2003-6 model but condition etc will depend on mileage service history etc. Purchasing from a Forum member will perhaps indicate someone who has looked after their vehicle and taken a genuine interest in its maintenance. Some however just join the Forum to sell their vehicle (Smails take note.........).
As for engine choice this again depends on your budget but perhaps more importantly what you can afford to run. 2.2 and above on the pre facelift models will give you the 6 cylinder engine which is a joy to drive. There are problems with rear springs breaking and roof problems.
Always check prior to purchase if the springs have been replace and/or the roof motor. Rear springs are relatively cheap to replace and some update all four with springs to lower the vehicle. Personally not in favour of this but again personal choice. Certainly check for broken springs prior to purchase - Normally the bottom coil which then sits in the spring mounting plate and rattles when you go over a bump!
Check the roof goes up and down smoothly - and delays hesitation etc MAY be an indication the roof motor is on its way out
As for options - within your price range I would look at overall condition and service history - if both these pass the test then look at what extras it has
Has already been said but a good set of non RFTs will give you better ride and handling. Matching set across all four corners in preferable but certainly not a stopper to purchase.
As for colours - all a matter of personal choice but some of the more exotic colours (and there are not that many...!) may be difficult to sell on in the future. Silvers and greay are always a good bet, easy to keep clean and look stunning i.m.o. when detailed and polished
If it comes with a hardtop all the better but negotiate it within the deal rather than purchase as an extra.
There are loads of aftermarket wheel options some good some bad. A good check of rims for damage etc is essential as is the right tyre fit. 108s are cetainly popular on Zeds (composite OEM BMW wheel) but can deterirtare with corrosion if not looked after.If refurbed check they have been split rather than just sprayed over :thumbsdown:
GOOD LUCK
unish: