Welcome to TBN!
The price is right if everything looks good on it. However, it's a bit small for what you have to do. You'll be at mowing a long time to get 15 acres brush cut.
The 1714 is an older Kioti model, and I've not heard of any problems with them, they have a good engine.
Just for the price, I'd buy it and get a larger one later on when you can. Make sure everything is operational, no major leaks, no major smoking after warm up, look for evidence of any radiator problems. Make sure you run the tractor for at least 30 minutes to let it get to full operating temo. If there's any overheating issues, it will show within that time.
Sounds like a bargain though. That engine should go for near 5,000 hours.
John