not sure if Kioti is in there. If you don't have access to a dealer blue book, I'd look online and see what the average ask is.
Figure ten percent less than that is retail, and wholesale 20 to 30 percent less than retail.
Ultimately it's like the old saying, something's worth is whatever a buyer is willing to pay.
Good brand, good reputation, tractor should hold reasonable value compared to other similar models.
Transmission choice could affect value, hydro or at least power shuttle would be best for loader work.