Hi
Joined tonight as I'm after a z4m coupe but also own a 7 series so thought I'd chime in, hence the first post about a 7 series lol
Mines actually for sale but more than your budget so won't bore you with details but here's my ownership views
Ownership info -
They are a great car with a good solid engine, not fast tho, it's more of a cruiser..... 0-60 in 7 and a half seconds ish
Options are pretty rare and there are a lot of standard cars for sale ( 90 percent ) , when you view them look for a separate instrument button panel just below the air vent on the right hand side ( where z4 cup holders are ).... If it has one then you have a few decent options like heads up display, night vision, stop and go cruise, lane departure warning etc etc. most don't have this and therefore have very few options. Also check for the camera buttons next to the gear stick
Dynamic drive and integral active steering are also essential but were 3 and 2 grand options so most cars don't have them, I test drove with and without and the difference is night and day. A standard 7 series without the 4 wheel steering will not be able to do a full u turn in a car park or a street without 4 or 5 attempts, the 4 wheel steering fixes this ( active steering ) but was a 2 grand option so again most don't come with it, dynamic drive does however come on m sport models as standard but optional on SE models, again it was a must for me and the ride was much tighter and more sporty with it vs the standard model I test drove
Cameras are essential, side and rear ones as the bonnet is so long you can't see oncoming traffic when coming out of side streets, it would be dangerous without
Soft close doors are a nice touch, sunroof as well, also the speed limit warning cameras are great ( scans the road for speed limit signs and displays the speed limit in the heads up display )
In my 3 years of ownership my 2009 had nearly 10 grands worth of maintenance bits and bobs so it's a pricey motor to run ( inspections 600 quid, brakes 600 quid for rear and 800 for fronts etc ) .... My air con compressor went - 2k.... Then I had the boot hinges replaced ( it opens and closes itself ) and that was another 2 grand.... Then I had the front suspension done which was ......... Again about 2 grand
Known issues I came across on various forums, leaking issues stemming from the LHD steering wheel cover in the engine compartment failing after a few years which can cause substantial electric damage, gearbox failure ( although pretty rare ) and the long wheel base versions have air suspension that fails after 5 or 6 years and costs approx 4 grand to fix if your using a dealer ( so stick to normal wheel base as they have standard suspension )
I loved it and am only selling as I have the new shape on order for Xmas , it's been the best daily drive I've had in ages, loads of road presence and you really do feel your driving a land yatch, think the dimensions are not far off the phantom
I put 21 inch bmw alloys on mine as it looks a little boring on smaller ones so tyres are about 1.7 k everything you change, 19 inch standards are still a grand or so..... If you stick with run flats... mine last 2 years ish
I personally would not buy one without a warranty, it's basically a massive computer that you can drive and literally anything that goes wrong will cost thousands,
A CPO one is a great buy at the moment, there are a few at 16 - 18 grand now that are nice motors and you get a 1 year warranty, bearing in mind a well optioned one is a 90k car.
Hope that helps a little, good luck with the search