Question: how much does it cost to turn a garage into a mother in law suite?
Answer: The Cost to Add a Mother-in-Law Suite to an Existing Home Garage: $20,000 to $50,000 (plus $15,000 to $25,000 for a bathroom): While insulation might be an issue to update, a garage already comes with framing and foundations and more than likely already affords occupants a degree of privacy.