Cabin 21 at Camp Erdman served as Ben Linus's home within The Barracks.
This profile view gives a better idea of how small the cabins are and how closely together they are packed. Once again the LOST crew did a wonderful job making the area seem grander on screen.
Sayid at the wrong end of a rifle barrel as he approaches Ben's (commandeered) home in The Economist.
Locke and Ben are playing those mind games together again in season 4' s Eggtown.
A night view of the cabin from Meet Kevin Johnson.
In the flashback to DHARMA days in the season 5 opener we learn that Pierre Chang occupied Ben's future home back in 1977.
In Some Like it Hoth we even see Dr. Chang reading to baby Miles in the home. I believe this is a composite shot with the exterior filmed at Camp Erdman and the interior filmed in-studio.
The season 5 bonus features include this shot of Chang standing on his porch.