How to select a building, move, and rotate it

I noticed that the best way to build is not with building tool, but with floor (pattern shape) and walls.

first you lay floors, give them the shape you need, move them around, rotate, etc, and only when you are ok with floors you place walls around them.

in this way, you can have different walls connected, odd shapes, and more or less whatever you need, rather easily but in a more flexible way.

If you use the building tool I believe the only way you can delete is by using the alt key with the building tool. You cannot select and rotate the only other way to alter is as you said the edit point tool.