With simply adding a wall in one bedroom then cutting out a door in the hallway would add a bedroom for us (somehow sticking a closet in there).

I thought this issue was resolved it is not resolved now I had to have a wall rebuilt that was ate up with mold luckily I have caught the water early this time and cut the drywall back so the only mold food is the bottom wood beam. 

We also painted all the walls, doors, and trim.

The nuclear tower stack had 3 climbing walls approaching 100M. 

tore away some sheet rock and every wall I've checked so far has a single 2x4 top plate.

After you prime, then you really inspect the walls and hit with another coat on any imperfections to avoid this.Do you agree?

Balconies, stairs, concrete, retaining walls, etc. 

If you need anything worked on that's hidden behind walls, floor or ceiling or the roof, it's going to get expensive quite fast.

And here I am trying to get better pictures and not to give away too many details but trying to have them clear out the pink and purple walls in the kids room!!

Older style mixes with some added sand works best.Outside of that, if you really needed to, you could replace sections with cement block or poured cement.As long as the walls are true and not leaning or bulging, then it's just a matter of maintenance on the mortar from time to time.