So can someone please tell me what a "two call" is?   I've read reviews of ladies I am interested in and they seem to keep referencng the same thing.  Thanks to all who help!

Basically two call system is, first call for general area of the incall, or the name of the hotel or apartment complex or major cross streets.  The second call is the exact address,  or room # or apartment #.
This is done to protect the ladies exact address. Many guys flake on ladies, however, the chances of you not showing up go down if you make the first call. And sometimes the lady can actually see you when you make the second call.   There are variations of the this system.  A helpful site for terms is www.urbandictionary.com. See the link

This will be near her location. Second call (from there) she will give you her exact location.

After arranging a meeting with a provider you will make 2 calls on the day of the appointment

1st call - when you are on the way to get the hotel/incall location they are staying at

When you get there....

2nd call - get the room number and the okay to come up.

Some advice on the 2nd call:

-Be discrete call from you car, she may ask you to give her a few minutes
-Don't call from the lobby with flowers in hand or holding a victory secret bag....
-Don't hang out in the lobby looking at your watch staring at your phone