Often plot plans are included in the mortgage documents received at time of closing for a property. Plot plans can sometimes be found on-line at the South Middlesex Registry of Deeds. There is a slight chance the Building and Wire Department may have a copy in its archives, but only if a plot plan was submitted as part of a building permit application for a given property. (Until the Building and Wire Department can digitize its records, there is a $30 fee for retrieving records from the archives.) Please note that plot plans are not reliable for determining property lines. Always consult with a registered, licensed land surveyor for accurate information about a property.