The errors abound in this ad.
I would not say that a Case GT is bigger than most garden tractors out there, would you? I guess that this seller has never seen a 400 series Deere. Of course, he is also wrong about the claim of 15" wheels because the "real" wheels on this tractor are 16" . He did get it right about it having hydraulic drive and that is a rare occurrence in listings. Most people use the "hydrostatic" word instead.
In my opinion, the tractor is most likely a 1968 Case 195. The positioning of the PTO seems strange to me. The tiller has been stripped of its safety shields and that does not inspire me too much. I'd value the tiller at $75.00 because of this. Simply put, the tiller is now a hazard looking for a place to have an accident with someone.
The front blade is not a Case item either and therefore put its value at ZERO because you might not be able to find anyone to buy it from you.
The tractor does have the optional E-30 Hylift kit and that's a bonus .
This is a difficult tractor to value due to all of the above. If the PTO is not OEM, then it has little to no value except to someone that wants to go rototilling with this tractor. It is missing both of the grille side panels but other than that, the rest of the tractor appears to be nice and straight. It always comes down to how bad you want this tractor and how scarce they are in your area as well as what you want to do with it. To me.... it's worth $400.00 to $500.00.