What you are describing is "bait and switch". This is a deceptive business tactic, and I would bail if someone up their advertised price when I show up.
As for the "bargaining" show a little class boys. If you know the price, and can't afford it, don't bother booking. You know what I'd love to drive a Porsche to work every day. But I don't go to the dealer, test drive it, and then expect to pay Toyota prices. Even more ridiculous is the amount that most of these guys nickel and dime for is less than they spend at timmies in a week. If you think a girls rates are too high, book someone cheaper. There are plenty of options in the hobby from 50-500 dollars. Choose what suits your budget.
I've been "hobbying" now for what? 20 years? Longer? (Actually, if you count rub-and-tugs, 26 years... I was 16 at the time! :Eek

.
I'm not a prolific poster, either here or (formerly) PERB, but this thread caught my attention. I think it's a great topic.
I've been fortunate: in all the times been with an lady, I've never had to a) deal with a B&S on price; b) had to dispute either price or menu items; c) deal with a dispute as to either her or my demeanor during or after a session.
I think I've been lucky, but as they say, luck is the residue of preparation: I'm as careful choosing a partner as SP's are in choosing clients. I do my research; I check the boards for recommendations; I don't seek out ladies that don't offer services that I'm interested in. I'm as careful as possible. I know that, in most cases, the lady on the other end of the phone/text/email is just as careful in choosing whom she meets. There are risks at both ends, but being respectful, cautious and above-all diligent in your choice of partner means that things like the above just
won't happen. It's not only sane...
it's unnecessary!
It's been a while now, and I'm just back in Hogtown again, but I fully intend on visiting someone soon. Be sure it will be someone from a suitable venue, with good recommendations, good reviews, and a menu of services that suits my desires. If those rules are followed, I believe, the outcome in almost all cases will be of benefit for everybody involved.