So a POT that I was chatting with said she would meet for a M&G if I paid her $200. I politely declined and explained that wasn't my policy. But then I got to wondering and want you gent's input. What if in those situations I said I'll pay the 200 and when we start the arrangement I'll deduct it off the first ppm. In a way that evens things out though we are still taking the risk that we pay the money and end up not liking the POT.

What do you all think of that idea?

The consensus here is don't do it.
And my impression is that the POT wouldn't do it and might be insulted by such an offer (if you care).
Most of these gals are rinsers, which means they will make money off the M&Gs and do nothing further, and it could be a lucrative scheme. They may be quite charming.
If she had any sense (and was a willing POT) she might listen to a reasonable argument: if we have an arrangement you'll come away with quite a bit more over time.  My guess is she won't bite, but worth a try.
It's always possible that we're wrong, and if you have a good feeling about her and don't mind losing $$ you could try and report back.
In any case do NOT send anything until you meet.

There will never be a "first ppm."  She will say anything at the M&G until you hand over the cash. Starting with asking for it up front.  

 
- If you pay on arrival, she will quickly make an excuse to leave and will block you.
- If you pay after arrival, she will smile, flirt, agree to anything and any allowance... until you pay. Then she will leave and will block you.
- If you refuse to pay at all, she will not show up because she has no intention of going BCD with you - ever.  
- If you refuse to pay and she then agrees to the M&G for no money, she may not show up. Or she may text you 10-30 minutes late and demand the cash to show up. Or she may show up with some unannounced friend(s) who will treat you with "extreme prejudice."  
-If you decide "Fuck it! She's just too hot to risk not paying." Then be prepared to lose $200 plus, drinks, gas, parking, time and whatever it costs you to find alternate method to knock one out in frustration.  

 
This is NOT speculation. This is the collective experience and wisdom of your fellow SD's. My advice: Just thank her for her time and pass.  

 
Life is good

 
The Cat