A man pleaded guilty to arson after investigators said he started a fire at a multi-unit rental property.The Sanford Fire Department was called to a fire at the property on Spruce Street on May 5, 2021. Firefighters saved the structure, but there was extensive damage to the building. Officials say the most significant damage was in a unit occupied by 49-year-old Thomas McGinn.When questioned, officials said McGinn confessed to starting the fire using gasoline and lighter fluid. He allegedly told investigators he wanted to "burn the building down."McGinn faces a fine of up to $250,000 and up to 20 years in jail.