Now, now. Most used Treks aren't worth more than a hundred bucks, because most Treks are mass produced stuff. But (and this is a very big but) the vintage steel lugged road bikes by Trek certainly are or should be. I'm with Lotek on this one fer sure. I'll maintain that the the 410/412 model, which usually goes for about 100-150$ on ebuy, is one of the great steals still to be had. I've got one which I have upgraded, and boy is it nice to ride. It's even pretty darn minty in the paint and decal department. However, the cost was sub 100$. The Treks pre-1984 are all pretty darn nice, be they Ishiwata, 531, or Columbus, but the first is completely undervalued.

Equipment on the early Treks could vary greatly, as they were available just as a frame. Mine has Shimano 600 Arabesque and a Campy/Rigida wheelset. Period, but not stock. Value? I dunno, but if I had to shave down to, oh, five or six bikes, I'd probably keep the 410. Four, maybe not.

A 720 is another matter; it's one of the great steel tourers and costs accordingly (theres a later 720 which is a so-so MTB, I think). In other words, be prepared to shell out the cost of several magnas or roadmasters for a 720 (and, in aesthetic terms, the 720 is worth an infinite number of those two fine brands).