On the first picture, I see the holes for a treadle belt under the handwheel on the right. $100 to $200 is a common price range here for a treadle in very good condition. Franklin is also fairly common and not as collectible as some brands. If you are thinking that is a fair price, ask for a picture of inside the cabinet. Make sure the pedal, fly wheel, pitman and other connecting parts are there. Also a picture with the front slide open showing that the shuttle and shuttle carrier are there. If this matters, remember that enclosed treadle cabinets might have a little narrower space for treadling than some of the open work treadles.
For that price, I would also expect the manual, attachments, extra bobbins, and no silvering on the decals. But that's just my criteria because I already have three treadles in acceptable condition and I paid much less than $100 each. As Cari says, if your heart flutters when you see it, that is an indicator!