Actually Bishop, why wouldn't you have a premium service that would allow 2 people to say be "Whitelisted"? Depending on the cost, it would be similar to the invites. If as a monarch I run out of the free invites I can pay $10 to get another one. If the cost and maintenance are so high, cover that cost with a fee.
oooo please please game mods let me invite (and pay) for my 'brother' to join my kingdom. please please please and my aunty and dad who all live with me. infact all 25 of us live in the same house. We will pay for them all.