...I'm not familiar with city-source gals. You say they offer in call/out call for VIP only. That sounds to me like they have a VIP status they offer. That isn't the same as the TER VIP membership.

You can look at the ads on the TER regional ad boards without having the TER VIP membership. Then you can check out the providers you find there by looking at their TER profile. Their TER profile page has a link to their ad or web site so you can check that out too. Since you don't have the TER VIP membership you won't be able to see everything about them but you can see some things.  I recommend getting the TER VIP membership. It's $30 a month. That's dirt cheap compared to paying for a session and getting less than satisfactory service or worse ripped off, robbed, or hurt.  Once you have seen a couple of providers you can write a review of the sessions and earn free days of VIP.

There are many agencies that will see you as a newbie. You don't have to have the TER VIP membership. They will want to screen you of course. If they don't I wouldn't recommend using them. Screening is for everyone's safety and discretion.

Check out the Self-Help Center. The link is on the upper right of the message boards under the red and white life preserver. Click on it and begin reading everything you find there. Even the stuff aimed at providers. It helps to know everything.