You can't go wrong with vous (formal) as in "Voulez-vous coucher avec moi ce soir?". 
Here's a fun hypothetical question. It doesn't work in contemporary English, where there's just one second person pronoun: "you". But many languages, like Spanish, have a distinction between familiar "you" and formal "you". Or suppose English had that. (It actually did a few hundred years ago with familiar "thou" and formal "you", but "thou" was lost to history.)
It presents an interesting, albeit somewhat fun, dilemma. How exactly should you address the provider? On one hand, what she does is a job, and you're interacting with her in a professional capacity. Not to mention, calling her by a familiar pronoun may come off as patronizing or objectifying. On the other hand, you're seeing each other in the buff and doing freaky sh_t with each other. In which case, using formal pronouns may sound ironic at best, and ridiculous at worst.
And let's not even get into the plural forms of "you", for when you're doing doubles. 
It's a whole other kettle of fish.
Thoughts?
-- Modified on 6/29/2016 10:23:25 PM
how I show up for the session. If I'm wearing a suit and tie, I would use the formal version. If I arrive in shorts and a polo shirt, I would use the informal pronoun.
I would envision the provider as a "shopkeeper" and the hobbyist as a customer. If I remember correctly from my travels in Europe, shopkeepers feel obliged to address their customers formally. Culturally, customers see shopkeepers as service people and might therefore address them with the familiar pronouns.
So a hobbyist in Europe might be okay addressing a provider with a familiar pronoun (e.g., "tu" or "du", as appropriate to her native language).
But wait! What if the provider is a dungeon domme? In that case, he'd better play it safe and use the formal pronouns!
When I lived in Europe (most of the 1960s) I had no money and did no P4P I did one trip with a provider decades ago and we availed ourselves of some local talent mainly in Austria. I also --again decades ago-- had occasion to hobby a few times in Germany and in Greece. It would have seemed really weird to use the formal form with the local provider just as on first contact with a provider here I can not imagine walking into her hotel room or having her show up in mine and beginning with a formal greeting. (Rather than a kiss and a hello sweetie: "I am most pleased to meet you madam" say I. Says she: "I too am most pleased to meet you kind sir". though that could be the opening lines in a kinky role play)
But I'm from Brooklyn and may --deep down-- just lack class.
But after any amount of communication it would be rude not to switch to "tu." I don't speak that much Spanish, but I suspect it's only slightly different. Because my Spanish is so poor, I only even try when I'm talking to a Latino who speak no English, which is extremely rare nowadays.
I think I'd do it the same way. So when speaking Spanish, for instance, I'd use "usted" when scheduling an appointment and at meet and greets, when the communication skews toward professional. But once the envelope lands on the table and DFK's are exchanged, not switching to "tú" would feel weird indeed. (Unless, of course, we're doing some sort of a BDSM scene, and I'm the sub.)
-- Modified on 6/30/2016 6:07:04 AM
I lived in Mexico for several years, and what you suggest seems perfectly logical. While I was not in this line of work there, it was not uncommon that even in professional relationships things went from the formal to the informal rather rapidly.
First email I would definitely address a client/provider in the formal, and the change to the informal, after that.
might that be considered semi-formal
The second person familiar is reserved for the Deity, royalty, small children, dumb animals, spouses and those with whom we have taken the "shortcut."
don Ozzie
However - a client asked to maintain the "vous" both ways during a session and there was something terribly sexy about bedroom talk using "vous". And, in role play another client will call me "tu" while I call him "vous", reinforcing the roles we are both playing.
So it can add a layer of eroticism to the whole encounter.
Languages are gender normative and patriarchal. Now I will go cry myself to sleep in my safe space.
In French, use of the tu-toi form can imply social position, as with an adult addressing a child, but it is alternately used to imply intimacy, as with lovers or even in prayer. Si je te m'adresse avec la forme "toi-toi" et tu ne l'aimes pas, j'espère que tu accepteras mes excuses.
and the problem my French teacher (A very lovely young lass I had a crush on already.) had in explaining when to use and not use the second person singular pronoun.
I was clueless to the hints, and so finally she made it clearer: It is for people very comfortable with each other. Finally, the light bulb went on.
I never did excel at French in any case.
The best I could come up with is: Come out in the alley you? I suppose that's how street walkers in Paris approach their clients
I thought about that too when I was preparing for my first mongering trip to Latin America (Costa Rica) and then realized that it was a non-issue once I got there. The chicas who approached me in Spanish always used the familiar/informal "tu" version of "you." Accordingly, I always used the "tu" form with them and never had any problems.
You raised the possibility that it might be more appropriate to use the formal form of "you" because you are seeing a provider in a professional capacity. That might be true, but the whole point of the session is to have or at least simulate a more intimate relationship, in which the formal form of "you" would be awkward. I think that this point holds true even more so in Latin America, where being a hooker is less of a formal profession per se and more of a lifestyle, and most independent chicas pick up clients in informal social settings, like bars, clubs, hotels, beaches, etc. A lot of the hookers there are not even full-time professionals per se but part-timers or just random girls who need to make a quick buck every now and then.
I think that the exception to this would be in a BDSM session where one addresses the other as "Master" or "Mistress," in which case the formal form of "you" would be more appropriate. I did have a BDSM session with a Latina provider in the U.S. once, in which the formal Spanish version of "you" (usted) was used.
Can you imagine approaching a chica and instead of saying "hola mami" you were instead to say "Beunos Noches Senora, como esta usted?"
Somehow it just loses something that way.
When I was a kid, it was not uncommon to here one adult male (as well as females) get another man's attention with a loud, "Hey, mister!" Used to hear it all the time where I grew up. I don't think it was regional. It was just like saying hello. But nowadays nobody addresses anyone like that. Haven't heard the expression for decades, except once or twice I might have used it myself just to see if people would think it was offensive. But, no, it's just old-fashioned.
And only in the past quarter of a century did people use, "Hey." I mean in place of saying, "Hi."
I remember researching a legal brothel in Mexico, for a trip that didn't materialize. I was chatting online with the scheduler, in Spanish, because I know it and wanted to practice. I used the pronoun "ustedes", the plural formal "you", in a sense of "your operation/company". (Familiar plural "vostoros/as" is used only in Spain.) Now that you said it, I might have been too formal; but she didn't correct me, so whatever.
Funny story. On a trip to Dominican Republic during my pre-hobby years, a provider in a bar addressed me as "tú". Silly me didn't realize she was a provider until she offered "un masaje con final feliz", which I refused, fearing local LE. (That's massage with a happy ending.) Most hotel workers, however, addressed me as "usted", even the ones older than me.
Silly you indeed, what that chica was offering you was 100% legal.
I still remember being in Costa Rica during the heyday, maybe 2004 or so and there was a cop at the Blue Marlin one afternoon, there was this really hot tica trying to get my buddy to fuck her for $60, the cop talked to her for a couple of minutes while all of were getting drunk and then looked at my buddy and said to him while nodding at the chica "cuarenta dólares" My buddy looked at me and asked what the cop had said to him as he spoke no Spanish at the time and told him the cop had said "good bye Joe" , my buddy was even more confused until I told him the cop had negotiated a price of forty bucks to fuck this smoking hot tica, and that's what I meant by "good bye Joe" it was time for him to get the fuck out of there and fuck that smoking hot tica. lol
As for the rest of the hotel employees, its really no different than in any hotel any where in the world, including the US. Almost all hotel employees will treat the guests with deference, but not the hookers, that is something universal the world over.
I just got back from a phenomenal mongering trip to Sosua, a significant hobby hub on the north coast of the Dominican Republic. (See the link to my recent post below). I plan to return to the Dominican Republic at some point and would like to explore mongering venues beyond Sosua at some point.
By the way, in my experience (I defer to the more seasoned GaG on this point), the Latina hookers that approach you out of the blue are usually not as good as the ones that you pick yourself. Either they are less attractive and need to be more proactive in order to generate revenue, they plan to fleece or scam you because they think that gringos are stupid and made out of money, or both. For a woman to approach a man like that goes against the grain of the machismo of Latin culture, in which men are expected to take charge. When a woman tries to take charge like that, something is not as it should be.
-- Modified on 6/30/2016 10:51:38 PM
It happened at a run-of-the-mill 3-star resort, around 2003. The hotel was private, but its nightclub (referred to as discoteca in Spanish) was open to the public; no bueno, in my opinion. As a result, local providers got in. I should have known something was sketchy when I saw one of them LFK the bouncer. As for why she hit on me first instead of waiting for me to do that, I was really shy back then, and she probably picked up on that.
Anyway, after she hit on me and I responded positively, we danced little bit. Perhaps she thought of it as a mildly fun diversion from working. Remember: I didn't know she was a provider. (Ironically, I've danced with providers at M&G's.) A short while later, she offered that massage. I panicked and refused, since I wasn't sure if the hobby was legal in Dominican Republic. Plus, I was on vacation with friends, that I knew were *very* anti-hobby.
(You know, it's kind of funny to be using hobby terms when talking about events that happened years before I discovered TER.)
You should use the formal "You" upon introduction but the informal "you" after cumming her in mouth... because by then you know her pretty well.
You can't go wrong with vous (formal) as in "Voulez-vous coucher avec moi ce soir?".
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