Totally excessive and expensive for the women who have to pay for it out of pocket!
Testing every 1-3 months a good interval, and most responsible providers are doing that.
I like Rina's approach - if one is especially concerned, they should request lower-risk practices like covered oral and no kissing on the lips. I would always be happy to honour someone's request to be more careful.
That's quite enough of this one. I daresay that a professional companion pays more attention to health and hygiene than 99.9% of civilian ladies. If you cannot get your head around the potential risks, don't play, it's quite simple.