If you have a friend that is "bike savvy" have them go w/you to check the bike over. check out the components--what type of brakes, rear derailleur, shifters, etc. is the frame rust free?
I believe your frame is made of a double butted chromoly steel (this is why it is light-weight). I have an old Kona that is made of this material. Love this bike, will never part w/it.
Are the folks at the Community Cycling Center helpful? Did they watch you ride the bike to make sure it fits? I am also a shorty, aside from the standover height--you also want to make sure the stem is the right length (in other words, you are not so stretched out to reach the handlebars that you can't control the bike as well as you should be able to + it causes back pain).
The price does sound a little high to me, but I don't know if the frame is in great shape and they put on new/good components.
Is there a warranty?
just some questions to consider.