SCOTCH PLAINS, NJ -- When Paul Lamastra started working full-time at ERA Suburb Realty in 1985, Ronald Reagan was in the White House, Live Aid raised $50 million for famine relief, and Michael Jordan was the NBA’s Rookie of the Year.

Since then, real estate prices in Scotch Plains and Fanwood have risen dramatically, as have taxes. The sizes of homes in the area have expanded ...