Little known but significant subsidiaries of AEI are Attleboro Enterprises Properties, Inc. (AEP) and Attleboro Enterprises Development Corporation (AEDC).

In the mid-1990s, the Department of Mental Retardation sought to close the institution, Dever Developmental Center in Taunton by moving residents and their staff into new houses constructed in their hometowns. AEP and AEDC were commissioned to build fully adapted housing meeting the needs of a significantly cognitive and medically challenged population. The construction of these homes would allow the State to close that facility, freeing up revenue for community-based services. AEI and its subsidiaries were one of three organizations approved to build those homes.

The homes built by these subsidiaries include wide hallways for use of adapted equipment, ceiling rails with lifts allowing staff to transport non-ambulatory individuals throughout the home, whirlpool tubs with lifts for bathing, and many other unique features.

In 2002, the last resident of the Developmental Center moved into a home AEDC built in the Town of Scituate.