While I can not and ought not speak for GaGa, I can freely discuss my own method plus reasoning:
First off to address something SftD has said about my opinion regarding hooker-like behavior to avoid any confusion. It is NOT my opinion that paying someone per meeting or per play equates the scenario to seeing a hooker, but it is my opinion that if a POT SB solely wishes to meet with the expectation that there will be an envelop for BCD activities, she's at the very least a quasi-hooker and just like the f.kind of fellas who have no intention of paying a POT SB any kind of allowances by gaming the system, this type of POT SB is a hooker in disguise who is also misusing the tenets of SA and SugarBowl in general.
My offer is very clear cut which is 1000-1500 per month allowance for 2-3 get together one night of the weekend. We would mostly go to dinner dates and retire back at my place. I do not expect an all day sort of affair and I certainly would not want to hang out with an SB for 24 hours at a time unless we are on a trip or something (only with longer term, established and trusted SB). I am willing to pick up such a POT SB on a weekend day's evening (if she's within a say 25 miles proximity) if she does not wish to drive over to me and I'll be happy to drop her off by about Noon on the following day, after we have had breakfast together. These are my expectations against the allowance so anything which she wishes to offer above and over that is her own discretionary choice just like any other gift and gestures outside of a cash allowance are at my own sole discretion.
I discuss the above with the POT SBs only when we meet (yes, I do take the risk of wasting time and money on say lunch/dinner but this risk does not phase me out) plus I do not advance the entire monthly allowance as I break that down to 2-3 installments. If she bails on me after one advance, I am out 500 which is a risk I am willing to take but the advances come after we have already been intimate as the first couple of times my agreement would be PPM with an expectation of a LTA.
The type of girls who I seek are the ones who are struggling with some basic expenses such as rent and car payments and those who are obviously single to accommodate toward my needs and time frame schedules. I am not on SA to be anyone's Daddy and I do not have the time for just playing the afternoon trysts / midday rolls in the hay (that were the case, I'd be in the 300-400 per meet range with a few SBs in my rotation). I am single yet busy so I seek something close to "dating" albeit very part time much more loosely based as opposed to full on traditional with someone in their 40's. What i pay for is the premium I associate for the SB bringing their element of youth to the table, not for what they're worth, yada, yada.
If any of this helps any one of you in your endeavors, feel free to use.