I am a long-time hobbyist and would love to be a regular with them. I would very much appreciate someone letting me know how I can become a customer. I understand their long-held public position that they're not accepting new ones but I also understand that guys drop out of the hobby, move, die. etc. so they obviously sometimes do.

I have found that being polite, and not pushy, opens a lot of doors

It's far more likely that you'll stumble onto a unicorn first before new folks are invited into the club.

They would not be available?  
Business is business, right?  

For almost obvious reasons such an offer would probably guarantee you'd never be let in

The problem for new clients at ILuvHot is not that the agency has as much business as it can handle, it’s security.  The owner is worried about law enforcement (LE).  Considering the number of agencies that have been busted over the last few years: Miami Companions and MiamiUltimate, and what has happened with Blue Flame Models?  Who knows?  The Girl Next Door closed overnight because Cindy was worried about LE.

They just post that "no new clients" for security purposes, and to keep the impulse calls from coming in.