All should be anywhere from 20-30 depending on options, hours, color, condition, exact year, etc...
I believe the the Xstar will jump in value a bit in 2001 because it got the better tower, in 2002 it got jabsco reversible pumps vs aerorater pump. Some in this era had vinyl problems I think so check that.
2000 SAN had the one piece rear deck, 01 went to 3 piece deck, 02 went to the narrower gunnels(larger interior) but no full wrap around and was also the last year of the GT40 I think.
If you were looking at 2002 versions of all 3 with tower, racks, bimini, tower speakers, PP, triple ballast, tandem trailer, cover, good condition and less then 500 hours you should be looking at 27.5-30 asking price and could potentially get for 25-27.5.