Are you a member of a Farm Bureau? If so, or if you can contact the Farm Bureau in the county where the case will be heard, you could look for an attorney to do your case Pro Bono, which means his/her services are free. Attys are expected to do a certain amount of these. I know that if it were being heard in Champaign Co., IL, where my DH practices, he, a fellow horseman, would at LEAST give you a free consultation to assess your case. You might find a horse-owning attorney who wants to help.
I'm curious, too--have you been served papers, or are you just being harassed? Is there a filed docket on this case? Look for the circuit clerk's site in the county where the buyer lives to see. Ours looks like this: Circuit Clerk of Champaign County, Illinois
You look for the name of the filing party. If there is already a filed docket in our county, you would look for:
Small Claims REMEMBER: ANYBODY can sue ANYONE about ANYTHING.
All they have to do is pay the filing fee, and the Circuit Clerk's office is happy to take their money. There is NEVER a guarantee to win a lawsuit. Lawsuits are a lot of work for the attorney, they want their cut, they often charge way over $100.00/hour to the person who is SUEING, so it often becomes more expensive to continue the suit than to drop it, and they are lazy, like everybody else.
Oh, and I'd pray about this, too.
I'll be you a nickel that guy is bluffing.