Hello
This question and answer on the MCCC site may help you
How do I prevent homeless Sims from moving into houses?
Several different things you can do, depending on how much control you want.
If you want homeless Sims to leave certain houses always open, you can edit the houses in build/buy mode and set the number of beds under lot info to zero. Sims will not move into houses that the bed-count is set to zero.
If you want no homeless Sims to move into houses, you can edit the “Open Houses” setting in MC Population in the “Population Settings” section. Setting this number to greater than the current number of open houses will result in no Sims moving into houses. The maximum value is 100 and setting it to that value will definitely result in no moves happening.
https://deaderpool-mccc.com/#/help/faq#AutomatedMovein