Hmmm.
If you are set on that bike, I think that I'd start lower - you just know that at minimum, you'll likely have to replace/rebuild the master cylinder and brake pistons and/or brake line, and even if everything is otherwise sound, you'll probably have various seals to replace.
When I bought my LS, it was about 7 years ago, but it had ALL of its parts, and was running/mostly road-worthy once steering head bearings and fork seals were done. I paid $2400. Now, it had been sitting in storage for an unknown number of years (minimum of 5 years, more likely 8-10)
By the by - I noticed someone near to one of my client's offices has a silver R65LS for sale - I noticed it as I drove by the house last week, but didn't stop to check mileage/condition. I can try to get more info on it if you are interested. I think that I found an online eposting for it here, though of course, there would be additional cost of getting the bike out to you:
1990 BMW
1990 BMW K1, blue/yellow, 10K orig miles, very rare historic K bike $7900; 1983 BMW R65LS, very low miles, very rare bike $2795; 1990 Honda VFR 750F, 17K, red/white, nice only $2495.
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