It is all about what someone is bringing and has brung to the table.

I am single, but target food and supply inventories for four people so that I can feed people who decide to be useful.

The real key to be able to take in the extra people you need for everything from farm labor to security once a retreat is occupied full time because the more you are set up for that, the more easily the survival retreat can make the transition from bugout spot to the kind of sustainable tribal community which will benefit you in the long run.