Alan,
I get your point, though it probably won't be practical to take the bike to a bike shop. I've done that type of thing with used cars, getting them checked out by a mechanic before buying it. It that common practice when buying used bikes? One issue is that we live about 45 minutes away from the seller.
I gave my friend similar advise about the value of used bikes. I think that $150 to $200 would be a more reasonable price for the used 7300, depending on the bike's condition and the quality of the accessories that are included. But I'm not really up-to-date on buying and selling used bikes. (I just bought a new Electra Townie, which is nice).
A new 7300 is likely beyond my friend's budget. However, I'd hate to see her buy some cheaper quality new bike that won't hold up. I almost bought a new Trek 7300 myself, before settling on the Electra, so I do think they are good bikes.
-Ted