Hmmm... I've never been in and out in 15 minutes, but I have booked 1/2 hour for $300 and left with my head spinning (in a good way).
On the flip side, I must admit at least one experience where I knew in less than 5 minutes that my $400 was not well spent.
Not quite on par with your experience, but I once did an incredibly informal M&G in the parking lot next to a coffee stand. The new prospective client only had 15 - 20 minutes to visit, at which point he left $200 on my dashboard when he got out of my car. We only talked, nothing more. No physical contact beyond a hug. He went on to become a semi-regular. $200 for approx 20 minutes? Sure!
ten to fifteen minutes was pretty much standard, but it was a hell of a lot less than $800.
It cost about $100 then to get your fries frenched.
And yes, I always left with a big smile.
I remember well the first time a gal said "Where are you going?" She let me recover for about 20 minutes then took me for another ride. I think she was my first real "favorite".
I'm in Vegas one night, I see this hot Blonde at the bar, she had guys all over her. She seemed to be the "life" of the party....So the next day I'm at the pool. I see her walking across from me on the other side, I knew it was her. She found her lounge chair, got settle, took off her sun dress and I had an OMG moment. I swam across to her and said "Hi, I saw you at the lounge last night"..She smiled and had a very sexy look when she replied in a very noticeable Russian accent. " Yes, that was me... and?"..I just said, "Would you like to go to my room?....Next thing it's 500, we shower together, we had our "fun". She hit it and quit it....Total time, maybe 45 minutes. Then we went back to the pool. Her at one side, me at the other.
Many years ago i was in a Mississippi Casino. I was headed back to my room, in a pretty good mood as I had just had a really nice run at the tables. A real hotty had gotten off on the same floor as me, so dog that I am I started talking to her, She was NOT in a great mood, in our brief conversation in the hallway she told me about the cheap ass who brought her there and who had promised to spend all sorts of money on her, but who instead was blowing all his money on the tables.
I had one of the corner suites and as we reached the turn I told her that I was sorry her trip was going so bad and that she should look me up later, instead of just saying yes or no, she responded that she'd "do me" for a hundred bucks right then and there, well we were no more than ten feet from my door, so what do you think I said? Within about 3 minutes of meeting her I was balls deep into her, and yes it was a hundred bucks VERY well spent. I think she did it more to get back at him than for the measly hundred bucks, but boy she fucked my brains out and the moment we were done she hopped out of my bed and it was the last I ever saw of her.
... a provider told me a couple of years ago. I had trouble believing it at the time, but your post confirms this kind of thing happens.
She told me the guy paid for an hour of FS (at the time she also offered FBSM at a lower rate). When he arrived, he told her he wanted a BJ. Sure, she thought, and gave him one. Then he got dressed and left, about 10 minutes after arriving. I should add she's incredibly hot with one of the best bods I've ever seen up close. She was incredulous. So was I.
But as I told her, it's his money. And she got 50 minutes of paid free time.
And FWIW, I've seen your pics and wild horses couldn't drag me away from you after only 15 minutes. 
...back in the day - before I started using verified providers only - I contacted an agency to send over a girl. I didn't expect the actual girl in the picture, but some sort of reasonable facsimile. The girl I had called about was a very pretty and curvy blonde.
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When the thin-as-a-rail black girl showed up at the door, I gave yer $200 and wished her well.
