I sell mine when I upgrade. I take care of my stuff, and I'll fix anything broken. If it is not worth fixing, it goes to the dump. I do clean 'em up, maybe even polish the hood. I usually get about $500 for 10 year old.
For example, if I was selling a 2018 Husqvarna GT52XLSi, whose original price was $3500, Assuming everything is immaculate and fairly low hours, It could be sold for around $1500-1800. So typically around half of original price. You also have to factor in how the older models from around 2015 or so were built better than today.Since The cheapest MTD mower is over $2200.00 and the Husqvarna is $2899.99 what would be a fair price for a good used mower? Around here if I ask $500.00 for one, they think you are trying to rob them. I don't sell junk I go over them and fix whatever it needs. Never have had but one complaint and that was an ignition module. Sold a really nice Poulan Pro 26 HP 48-inch garden tractor that new was around $4000.00 I won't even tell the price I sold it for way too cheap. Did not want to winter it over. Have a nice Dixie Chopper Iron Eagle 23 HP 44-inch cut asking $1800.00 for it. Changed hydro filters and fluid new expansion tank deck belt spindle bearings in one spindle new deck and motion idler.