I’m currently working on a set of modular walls for a game: I tend to create several different sizes, and also different angles for corner combinations (15, 30, 45 deg, etc.). I’m sure there’s a way to automate this, but I’m not able to think about the right process here. Automating this would also rule out metric errors (like me messing up the grid).
This is what modular kits look like:

Basically, I was looking for a way to generate a set of base meshes (like, just optimized rectangles that respect the grid), which then I can use to start detailing (by adding moulding, greebles, etc). Automating the base rectangles for different sizes (1m, 1.5m, 2m) and also with the CSG for windows, doors, etc.