Yashica TLRs were made with a few different lenses. The Yashinon is generally considered the best of the Yashica TLR lenses, but differences may be minor. The big thing to verify the condition/accuracy of the shutter. Leaf shutters (as in most, if not all, TLRs) like to be exercised on occasion. Make sure the little focus magnifier pops up properly and stays up. Make sure the focus distance as shown on the focus knob is close to the distance to the object you're focusing on. Finally, make sure the film winds correctly and does not overlap. All this applies to any TLR, with the exception of the Yashinon lens.
$100 is optimistic for a Yashica in good condition, but you might get lucky.