I am traveling with a group of 15 people on a Mediterranean crusie. I have arranged a few private excursions with tour companies. Some of the trips are just transport from one place to another. Other trips involve a tour guide. Are tips expected? If so, how much? I thought it would be better to collect from everyone ahead and give one tip to the drver or guide. Any thoughts on amounts?
Here are tips on tipping in Europe: http://www.ricksteves.com/plan/tips/tipping.htm