Looking for best house design extension

I have not discovered a single extension that handles all phases of residential construction, typically a collection of extensions provided by a developer, that interact. Most are paid with a few that are quite expensive, targeted at commercial users. You might check out the Medeek Extensions (my favorite) and/or John Brock’s extensions. I am sure there are more but those come to mind first. If you do a search you will find many more and some very knowledgeable professionals. Also, of interest in evaluating the extensions would be YouTube videos (SketchUp Essentials, MasterSketchUp, SketchUp Skills (Aaron), etc.). Try searching this forum, there are many posts. Here is an example:

Hope this helps …