As a land Tour Guide of many years experience, I hang my head in shame when I hear that my colleagues act so unprofessionally as to beg for tips.
We are paid for what we do - not handsomely, it is true, but adequately. My reward is to give people the best experience that I possibly can on the tours I conduct.
At the same time, a tip is a very tangible way that appreciation can be shown. I have received some very large tips - as much as $50.00 from one person. On some tours I have been completely skunked. When this happens, it makes me feel that I have failed and I return home disappointed - with myself.
$5.00 is a good tip and would be well received. If one isasked for a tip, then $1.00 is enough - maybe too much! Think about how hard to guide has tried to make the tour a good one, then tip accordingly.
The driver? I always split my tip 50/50 with the driver. He deserves it!