I bumped into similar issues - most kitbash modes i use are detailed down to screws. I remesh them or blender simplify them or drop the details. It is somewhat time consuming but nowhere near the complexity described in there. And for a building you dont need that level of detail.
We experimented with a similar process in agriculture for customer VR tours of facilities that are too remote or would result in excessive biosecurity risk for the plants/animals inside.
However, we now just use 360 degree video to provide a better, more realistic experience. it's not helpful for exploring designs, but its a better choice (IMHO) for tours of facilities that already exist.
Texturing is trivial if you don’t care if it looks good. Texturing and lighting are an enormous amount of work if you’re using the model to sell or impress people.
Substance painter and procedural materials work wonders. Plaster, bricks, marble, glass look great. And render nicely in ue or unity +hdrp. It can bake normal maps, ao, and so on for high fidelity. Worth giving it a go. Tho you need to uv your models in blender with marked seams or use triplanar textures.
all of these tools exist and you're totally right they work, but they aren't trivial and require time and skill to do properly. I was responding to the idea that this kind of texturing and lighting is trivial - its not if you care about the product and actually want to sell based on it.
