ModuleModo

I made it to build low-poly house kits without modeling the same wall a hundred times.

Pick a module (window, door, entrance, balcony, loggia, corner, bay window), set the size, and Blender builds it: plane, inset, extrude, the way I would do it by hand. The mesh stays clean and light, with quads and triangles only, no T-junctions, and shared vertices at the seams, so floors and walls snap together. UVs and smoothing are done for me, and I can change any size afterwards.

Blender 5.2+, free, GPL.