It's an older bike (late-'90s, early-'00s), but the Trek OCLV frames are durable and ride nice (I have a 1999 OCLV MTB that is beat to hell, but still rides great). The mix of components is a but curious, and may or may not be indicative of other issues. I'm guessing the 9sp 105 components are original. As mentioned above, the 10sp shifter and 9sp cassette thing raises a flag, but maybe not a red flag. The cassette is also a pretty tight range. If you're planning to do a lot of climbing, or the hills in your area are steep, you might want to replace it with something with more on the low end. I've seen these bare frames selling for similar prices, so this price isn't out of line. However, you may need to throw some more money at it to make it right for you. This has the potential to be a very capable road bike.
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Platypus gravelus.