Control over a random spawn system

In my project, I use a system with which buildings appear randomly in an area, but I have no control over it. I would like them not to overlap each other. I would also like, in certain areas that I determinate, they not appear.

Yes, it sounds complicated haha. The system uses different levels, in which I place different buildings. The attached blueprint loads, repeat and distribute these levels, with their respective buildings, in an area

This is the blueprint of the level:

PD: sorry for my english!