Jesus christ, this game never seizes to amaze. Not only is the person behind it creative, but also create the tools for other creative people. Edit: one person, not people, I was too lazy to Google and didn't remember.
I used the wall builder to make a little loft above the shower in the main room. Put up some custom wallpaper posters, put in plant pots and some glowsticks, shove a bed and plasma TV in there and it's all cozy :)
you can break built stuff with a hammer, just like models though I'm pretty sure the size of the object directly relate to how many hits it would required. Something I couldn't discover is how to remove the blueprint ghost things if you decide you no longer want to build something there. As far as I am aware you gotta build something just to remove it.
You know, ironically the only command the game doesn't tell you is to hold shift to actislly enlarge the shape. But to include the special brick builder you get in sandbox And, the building example is really effective. I assume however you can break it considering there's a wall fixer. But that's in WIP. But with that being said, I hadn't properly tested it so I'll do my best for it