I’d be more concerned about the hrs vs the miles. If a guy is using a wheeler strictly for plowing you’ll see something like 100hrs and very low miles – but those hrs were much more demanding on the machine vs 100hrs of cruising the farm or gravel roads.
15k miles on a machine that’s never had any maintenance is also a factor – regular oil/fluid changes, greasing lube points, belt, cleaning and replacing the air filter, etc. all add up.
If you’re buying used private party, show up early – folks tend to get stuff running and warmed up before people show up to mask cold start issues. Take it for a ride, get it to full operating temp and make sure it starts, stops, turns, shifts, lights work, fan works, etc. Pull the seat and check for valve noise and exhaust leaks, check the oil, check the coolant. Make sure it has a title and I wouldn’t buy anything snorkled – most folks snorkel them after its been sank lol