Is it legal in the state of Maryland for a landlord to sell a property and tell the tenants that they have thirty days to move out.

It is perfectly legal for the landlord to sell the property without informing you beforehand. Once the property officially changes hands you need to be informed of any changes as far as who to pay rent to, etc.

Whatever lease you had previously is still in effect. If you were a month - to - month tenant, then yes, you can be given 30 days notice to terminate your tenancy regardless of the reason. (Unless your lease or state law require something other than 30 days notice.)

Are you month - to - month, or in the middle of a lease, etc? Do you have a written lease?