1st, this is an e32 chassis, not an e38. there is no subforum for the e32, so i guess we just sorta stick around in the generic 7 forum.
there are quite a few of these around, but not too many with the manual. at least not in the north american market. that could be either bad or good, depending upon how you feel about that. they're a heavy car, but have decent manners. (btw, i like manual cars...)
prices for these tend to be all over the map, depending upon documentation, age, miles, and such. if there is a discrepency in the actual mileage, then that would be a detraction on the 'value' in the eyes of one that looks at such things. the reality is it's almost a 25 year old vehicle. i would look for similar e32's and compare with them.
in the end, a proper pre-purchase inspection should be done if you are seriously considering this for a dd vehicle.
you could also check over at e32.org for additional information. they've got a larger e32 following.