First let me say that I pretty much only session with established independent Dommes rather than at 'houses'.

I view indi Pro Dommes as professionals free to set their own fees, much like a lawyer, accountant or a skilled trades person. I really don't feel tipping is appropriate or needed any more than it is for other professionals you have hired at an agreed upon rate. I don't "top up" my lawyer's or accountant's invoice.

Having said that, I will sometimes bring a gift of wine, perfume, chocolate or other small item from a Domme's wishlist if she provides one on her website.....especially for Dommes I have sessioned with often and am friendly with....( more as a token of respect and admiration than a financial transaction)