There are some impressive Dommes in San Francisco - both skillful and beautiful. The two detailed here are for sure! But, Mistress Oksana's rates are 2X higher than the current "normal / typical" rate. Not knocking it - if she is that good, and has steady business, good for her. But, I just have to believe you can get similar at current normal / typical rate.
I have seen some Dommes having premium tributes and usually assume it's indicative of their being a more hybrid provider but I'm not sure here.
She is in one of the most expensive areas of the country, so I would expect her tribute to be higher. Or maybe she is just going with the quality over quantity method?
Either way, her practice, her rules.