You have to make sure you have the people you want to move doing nothing and you have $8000 simoleons. If someone is living where you want your person or family to move, then you have to make them move out of town or make that person or family move to another house by making a new one and scroll over to the right and you see that there is an option to move household which costs $8000, like I said you needed, or, if you want to move a single sim, there is one called move existing sim. I'm happy to help if you have any more questions. But, I am not a geek, so I don't know everything. ?