I wouldn't rely on the TER info simply because its only as accurate as the guy who entered it.  If nothing on the website then you don't have a choice but to ask...just do it discretely.  Try something like "about the envelope" or "there isn't a donation amount listed on the website"....or you could leave her $1000 she won't object!

is to say, "I couldn't find any donation on your web site but I did find $xxx on TER, is that the current rate or might you be running a special?  Sometimes a lady will list a 1-hr. rate and a 4-hr. dinner date rate.  If you want 90 minutes or 2 hrs., you can ask "I'd like to see you for 90 minutes, can $xx50 work?"

Whatever you do, do NOT try to negotiate a lower fee from what is posted or what she says.  Do NOT say, "I understand your rate is $400, but I only have $250.  Will you see me for that?"

But it is a problem if there is no mention on her site.

Often the best suggestion is to see someone else but if you have to see this gal, ask her how would you go about finding out what her donation is and see what she says.

If unsure, you can discretely ask or ask for a link to her most recent ad.  
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