My WildStar community can have 17,500 decor displayed on the exterior. :) SE needs to improve their programming skills/train their hamsters more.
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Here's a shot of the community myself, my husband, and a friend of ours worked on. You can see a lot, though not all, of the community from atop a hill in one corner (not visible due to the fogginess of the sky we chose: a bunch of a fancy Dominion enclave including shops/homes/restaurant/etc, a floating "college", a city made of shipping containers). It's made of 5 housing plots smushed together with a common area between them. Everything is custom built.