I live in California and travel annually to Maryland where I own and rent a house. When I travel, I purchase a roundtrip airline ticket, fly to Baltimore (BWI), rent a car and drive down to St. Mary's county (90 miles) where the house is located. I usually stay at a local hotel and drive back and forth to the house and local hardware store for supplies. When my business is done, I check out of my hotel, drive back to BWI and fly to California where I reside. The total miles I drove are conveniently listed on the completed receipt for my rental car. Can anyone tell me what I can claim as business miles? What are considered commuting miles here? This is the ls last question I must answer to finally complete a return from 2010...help!