Eviction when house sells We have rented a house on a farm for over 7 years on…

Eviction when house sells
We have rented a house on a farm for over 7 years on a month to month basis; no lease. Landlord has told us in the past that he would sell to us, but just sold the whole farm, including our house, without notifying us before putting it up for sale. He then told us that if he sold the farm w/o the house, we could buy, and if he sold the house too, he would put in the contract that we had 90 days to vacate. He just gave us a letter stating that we have only 50 days to get out, and asked us to sign the letter, which we did not do. Is there anything we can do about the things he has promised us and not stuck to?