Maintenance responsibility for elements on the border of lots within a planned development (often called “party walls”) is determined by the governing documents or, where the documents silent on the issue, by general rules of law. In most cases, each of the bordering lot owners is responsible for a percentage of the cost which reflects the extent to which the element serves his/her lot. Any of the bordering lot owners can undertake necessary maintenance, and recover the appropriate share of the costs from the other bordering lot owners.