So one of my atf's I was planning on seeing tomorrow unfortunately had to cancel. I could connect with someone I've seen before but thinking of trying someone new. As I've been searching reviews and looking online, I notice a few different providers that they have different prices. For example, there's two ladies on p411 who have prices that are more expensive than on their Tryst link ad.  
The price difference is like 50 bucks per hour, so which price would be considered the actual price of service or should I reference the ad in which it has the lower price?
My guess is that provide either raise or lower their price on one site and forgot to make the same adjustment on the other. Thoughts...

So, it's possible their rates are higher on P411 because they view clients from their as likely to have more disposable income.

And then pay that rate.

411 has a policy for providers stating they cannot charge higher rates on other sites, so the listed 411 rate is the max she can charge without getting a partial ban, or delisted, from 411.