We had 20+ cats back in 2000 until 2009. Then we moved to another house just a block away from the previous one. But the cats didn't move in with us, and they all left. Some went back to the old house, and I don't know what happened to the others. Maybe they were thrown away by the owner of the house or even killed.
How did you manage with 20+ cats? For now 10 cats is already waay too much for us.
The whole family loves cats, esp. my sisters who had their favorites among the pack. Then our aunt who lives across the street lent us two big cages, and we taught our cats to sleep there. We just left those cages open so the cats could come and go as they please.