You're in the ball park but in my opinion, I think US $20K - 21K is appropriate with the included attachments. US $18K is a deal for the buyer at 700 hours and the add-ons.
I have a 2006, 7800, loader and mid-mount mower at 275 hours. I'd be hard pressed to let it go for any less than $18k, even though that is what I paid for it in 2006.
Can you replace your 7800 (if need to replace) for that? That is a fairly nice mid-level setup. That 7800 is tough and at 30 HP, just right for medium duty projects.
My 7800 has never needed one single repair. Nothing.
Batteries, fluid changes, tire inflation checks, greasing, and cleaning is all I have done to it; all self-service maintenance.
Best on the sale. It will go quickly at that asking price.
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