This is a procedural building generator for Blender 3.2.0, made using geometry nodes.
It works on meshes, meaning you can use the standard modeling tools in Blender to quickly create a render-ready building. You can also take an existing (low-poly) mesh and convert it to a building.
Since it's a purely geometry nodes-based solution, it doesn't have access to all the information about the mesh that it would ideally have, but I've been able to find workarounds for a lot of things (for example, finding the width and height of a rectangular-ish face).
It is available on Gumroad here: https://coan.gumroad.com/l/buildinggen