I just bought a 2005
B7800 w/ 200 hours in NJ from a Kubota Dealer. The price was about 2.5K less then a new
B7800 with identical options. That comes out to about $13 per hour of depreciation.
If you carry that formula over to a 600/hr machine, you should get about $7800 off new MSRP, which doesn't sound right to me, as thats almost 50% off. It's easy to see that the $/hr value decreases as the machine gets older, in other words, they loose more value per hour when they are newer.
200hr and 600hr are far apart, it's difficult to compare w/o a depreciation spreadsheet, especially w.o the actual prices. Ballpark, I would expect something like a $2500-$3000 difference between the machines, so I would say the price sounds about $1000-$1500 high. Thats more along the average of $8 per hour.
Just make sure the machines are truely identical. If the 600 hour machine comes w/ loaded tires and remote hydro, where-as the 200 hour machines does not, that would bring the value difference closer. In my recent searching for
B7800, not many used machines I've seen have been identical.
FYI I would say about $10k - $10.5k for the 600 hour machine and $13k - $13.5k for the 200 hour machine (I paid $13.5 w/ warranty and 0/42 financing). Thats tractor+FEL+loaded R4+remote hydro.