... looks like anyone who has a tractor forsale in my area want 2-4000 less then you can buy a brand new one for. even ones that are up to 10 years old.
That's a common problem. Most folks don't want to take the hit on depreciation when they decide to sell. Even if it's an old machine. Figure how much you're willing to spend, then start negotiating. If you can't get it for what's within your budget, move on and don't have any regrets.
Always leave something in the budget for repairs. You'll have to do some things to get virtually ANY used machine working the way you want it. I had a $10K budget, got my tractor, mower and loader for $8300, have spent about $300 and figure on spending a few hundred more. Still under budget and loving it.