Help,Can an owner Reneg on a land contract and sell to some1elses

[Nate Adams]

So my friend is having an issue, and I am trying to seek your guys help in the forums.  My friend writes..

"So i am purchasing a home on land contract. VERBAL TERMS of said contract where in lou of a large down payment instead my first year of good rental history was the down payment, which i have not defaulted on payments always made on time or early. i should also add that since ive known this man many many years this entire contract was made verbally and a handshake to seal it.... Not smart i know. I have updated a few things in the home at my own expense. Drywall, shower fixtures, electrical outlets etc. Again at zero cost to the current home owner. Now said homeowner has recieved a generous cash offer that i cannot match and is making every attempt to push me out of my home. As said before all payments are current so he cannot evict for non payment. He has gone as far as stopping at the house on an every other day basis to basically harass myself and my wife, making complaints about the property as an excuse to get in. Now he has crossed the threshold by calling the health dept. To come inspect the home for black mold which he knew was there when we moved into the home. Now my understanding is if they do find mold myself and family have to vacate the premises. What are my options???? Thank you in advance."