If sociology had not been a punchline at my university I might have majored it in it because I find this thread absolutely fascinating. There are such a wide range of responses...some typical and expected, others more personal and thoughtful than I would have thought possible. Nuance everywhere. Who'd think us degenerates capable?
I've been low-key thinking about this thread since SB posted it. Or more specifically, how I personally would feel about it and what my words of wisdom she asked for could be.
So, wisdom first: I think out of all the comments left here, lightweight's is closest to my own opinion. But I also agree with Hollander's warning about mixing business with pleasure, which is something lightweight echoed in his. You asked if it was wrong to call someone you met in the "business" and proposition them with a certain arrangement. My answer to that will always be there is never anything wrong in the way two sane, consenting adults choose to interact with each other. The worst that can happen, at least initially, is your proposal is politely declined.
As others said, should both parties go forward, communication is critical. As long as you are both continuously honest with each other about what you want, and how you feel, I think the danger of any of potential pitfalls is lessened. Maybe I'm wrong, but I get the feeling that you're not talking about a random late night booty call here when you're feeling unsatisfied or turned on. Seems more like you want a cherry on top of your ice cream sundae, the kind of physical engagement that makes a bad day good and a good day better. But that requires a spark, and they can be fickle beasts...so I'd be careful. When things like this go sour, it always seems like it's because of mismanaged expectations. Your someone should understand that your arrangement can change quickly - that you are entitled to feel differently tomorrow, next week, next month. Or even the minute they walk out your door. If this someone can't understand that, there won't be a happy ending (ha). I also think it's important that any future rendezvous are initiated by you, not the object of your desire.
You also asked us in your post, is this something we would run to or run from? Me personally, I would not run to it. An arrangement with any provider, I mean, don't take it as a referendum on you. Partially that's because I don't engage in this hobby for the sex itself, so my opinion is that getting it "free" is only appealing to those who a) can't afford to see providers as often as they want or b) aren't already getting it "free" elsewhere.
That being said, I wouldn't run from it, either, especially with someone who I know isn't afraid to be honest. I'd consider it with an open mind like all other things. I probably would try to compensate her for her time anyway, at least at first. If she refused, then I would want to make these "booty calls" about her needs. In a paid session, it's about what the client wants, right? So in order to make a distinction between business and pleasure, I'd want it to be about whatever the provider wanted. If I want to dictate the way it goes, I would call, schedule an appointment, and now it's a temporarily a business arrangement again.
Just some thoughts I had.
Wish you the best no matter what path you choose