Indeed Barbara - I was clueless about how much to offer. I did finally understand, after much consternation, (and useless jabber back and forth) a "bribe" was required. I knew a bit of Czech - but not enough of the "hard Russian" to get by so my friend had to speak with them. I put out Rubles and Dollars and Euro's fanned out in my hand. He took a selection and we got what we needed. When I found out it was over $200 total I almost hadda heart attack! Now I always travel with conversion tables I can take out - and I make sure they see them. (I'm not so good with doing conversions on the fly in my head - sorry to say) Even so, I should've known anyone wanting a bribe wasn't the most honest man on the street. This was years ago - but I'm sure cracking down on bribery and allowing "free" unfettered travel through Russia is not foremost on Putin's wish list. They still wore their rifles out across their shoulders, so I guess we got off easy. Anything for dollars or Euro's I guess!
BTW: In Italy prior to the Euro - I took out my conversion card, but the cab driver only took his fee not seeing what I had in my hand - I thanked him with a 50% tip for his honesty. (I'd studied Spanish, but not Italian - so he could've ripped me off good - even another Romance Language isn't totally translatable! So I was glad I'd gotten him. He gave me his card w/phone# and I used him for all my other travels while in Milan. I bought sweets for his 5 kids - whom I'd met - and he brought all my packages to my room for me which he didn't have to do - but I guess he knew by then I was a soft-touch! Thank goodness he knew more Spanish than I knew Italian!)