10 - 15% is probably average, but that number can increase or decrease depending on a ton of variables you will see once you get there. For instance, you are talking bear hunt so has the guide been baiting for a few weeks in advance to lure those bruins in? Just what does the guide do after you make the shot? How well does he take care of the meat to make sure it's good for your trip home? Do you have cold cereal or hot eggs and bacon every morning? etc... you can judge for yourself what you think when you get there but that 10 - 15 number is a good baseline.

Good luck on your hunt