I think the 18.5 is maybe a tiny bit high but in the right ballpark considering it's in Alaska and there aren't too many BMW dealers within your reach, so not much competition.
At Pandora Motorsports in Tenn, (they couldn't have been nicer or more accomodating) I traded the K1300S I won in the BMW Superstakes for a loaded 2011 RT with the remainder factory warranty, the BMW color matched trunk, audio, ESA, ASC and some smaller items like barbacks, cylinder guards, hiway pegs. Picking it up later this week and I'm paying 17,995 and am very happy (of course). Maybe offer them 17.9 and see what happens.