99,000 miles is a lot for an N20 engine that is on the original camchain. If it has been replaced then happy days.
The E89 Z4 has a VERY complicated roof and they do tend to be quite 'troublesome', especially after a lot of miles as wires can break due to many folding and unfolding actions.
M-sport suspension is VERY hard on the E89 and they suffer badly with wheels that crack (mostly the 19" 296M and 326M wheels).
The E89 is not a sportscar. It's more of a 'small cruiser' IMO.
I have had two E89 (both N20s) and they are good cars (I love the looks; they are pretty) but can be expensive if and when things go wrong; like the roof or camchain!
£8 is a bargain, but £8,000 is a lot for a 100k mile, 12 year old 20i TBH.
The 2013 alpine white one we had was a great car, though. It didn't cost us a penny in nearly 2 years (it was a very low mileage one though). Here's a picture to whet the appetite.
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