Adressing the roots of the housing problem

[Avatre]

I'd give up my second house if my alt could use my mains house.

With something like that though(and this is something I personally can't answer, for two reasons: 1. I don't have a house; 2. I don't use alts), is it possible to give a trusted friend tenant designation, and then increase their powers to invite other tenants, thus letting your alt become one as well? Or is that only something FCs can actively do?