Medical practice needs suggestions to prevent customer loss due to building for sale (business not for sale)?

The owner of the building placed a for sale sign in the front of the medical practice. The building is for sale, not the practice. We are here to stay. Potential patients driving by will see the GIGANTIC real estate sign and think to themselves "that practice is leaving, I'm going to seek elsewhere." We are forseeing this becoming an issue and losing new patients. Landlord is unwilling to take sign down. Any suggestions would be greatly appreciated. Thank you.