> You basically have to blindly buy a file if the description's interesting.
Not really. Most hypnodommes I know of have 30 second to one minute samples, at least for audio recordings. Then you have other people's reviews and testimonies on sites like this to help you decide. (I never bother with reviews on their own sites - you'd expect them to be somewhat biased in favour of the person brainwashing them, but these ones are comically boot licking.)
So, in that sense, being able to sample previews and review testimonies are no different than other media like books and films. Only real difference is it's not as mainstream, for obvious reasons.
Plus most hypnodommes give away the initial recording that sets up reinduction triggers etc, so you can also find out if their style works for you.
"Fair price" for hypnosis is extremely subjective, not least because we usually* don't even know how long they take/how much effort they put in producing a file.
* I'm sure some dommes will have given details
Plus, if you thought, for argument's sake, that $20 for a file was "fair" because it took the domme two working days to script, record, edit and add all the sparkly audio effects, would that mean another domme charging the same figure for an equally good file that took her one day to make (because she's that much more efficient) was *not* asking a fair price?
The guy who makes the BS file spends months putting in the effort and, if you've ever seen the images of his audio editing workflow, has an insane number of audio tracks running throughout. He gives his content away for free to the public (though he does have an early access patreon). Does that mean any hypnosis file requiring less effort but charging an upfront fee is not asking a fair price?
I think the simpler thing here would be to say what *you* are willing to pay, per minute, for hypnosis files and see if anyone can give you recommendations.