Established in 1982, NAI Southcoast is the oldest Commercial and Industrial Realtor in the Stuart and Treasure Coast marketplace. As such, we are uniquely qualified at delivering superior and tailored commercial real estate services beginning with a solid base of brokerage and leasing expertise, transaction structuring experience, property management and operational practice. NAI Southcoast. Instrumental in and committed to the development, growth and continuity of the Treasure Coast for over 30 years.