I think one thing guys forget to add is "to me". That sp or woman is not attractive to me. Because I think it is pretty obvious that she is attractive to many others, especially when you see her features praised in a review, but the next guy goes and says, for him, hell no. Except he doesn't say, "for me, no thanks" he chooses to claim that she is simply not attractive. Last time I checked, no one else can tell me what I can see as attractive, and having the debate in the first place is endless.
For the OP, I know I didn't answer your question, but really I think you did the right thing by giving her something for her time. I think the amount given should depend a bit on what the amount you were going to pay, still even just 50 is enough for the time you spent and would cover any costs she might have being there (since you don't know if she pays for her space like that or not) If you might have spent 400 plus, then the 100 is probably ok, if it was going to be 250 or less, 50 should be fine, and 150 or less, then 20? Other threads on this topic say just be polite, your reason is simply that you have changed your mind, apologize for taking her time, and present the amount. NExt time you will know to keep a smaller amount handy for this lol.
If you feel she has really deceived you in her advertising pictures or description or services, then I personally think that you should say something about that and leave by saying you are not going to stay and that no compensation should be made. For an sp who does not show face pics, most of them, and you simply are not attracted to her type, then it is not something she tried to hide or pretend about imo and she should be treated well even tho you are leaving.