Ross and Rachel live across the street from each other in a townhouse style condo community. Their addresses differ by one number (636 Park Ave. vs. 635 Park Ave). They both have decks off the back of their townhouses, and both decks are in need of substantial repair or replacement. Owners of townhouses in this condo community are responsible for maintaining their own decks as this is not considered to be community property of the condo association.

Ross calls a contractor on Monday, and the contractor agrees to come out and repair/replace his deck that Friday. Ross will be at work, but tells the company that Friday will be fine. Ross also tells his neighbor Rachel about the contractor coming over in passing conversation.

Early Friday morning, the contractor and his crew shows up and begins working on Rachel's deck instead of Ross's. Rachel comes out and offers them fresh-squeezed lemonade and ham sandwiches, and they heartily accept.

Upon completion of the work the contractor knocks on Rachel's door and asks if the man of the home is present so he can get paid. Rachel breaks the news to them that they replaced the wrong deck, and they have 10 minutes to get off her property before the police will come.

Is Rachel obligated to pay the contractor for its work? Do they have a contract? If so, why? If not, are there any other theories of recovery available to the contractor if he wants to get paid?