How do you usually use the terrain tools? And how often?

I've only built once after the terrain tools. I made the house where I was born. There is one entrance with stairs and another that leads to 0,5 floor (sort of) which we can't have, so I raised the terrain to have that entrance on the ground level and create the illusion that I needed. The yard was a lot of work but I'm quite pleased with it now. Maybe I'll post a pic later.