Well, I haven't chimed in for a bit, so I'll give this one a try.
Tips to get your money's worth:
First, do make sure they're licensed, both by the state and the Coast Guard. Not only is that the law, it means they are trained in water safety, CPR, etc. Though rare, bad things can happen on rivers.
I haven't bought a guide for years, but the reasons I did were to learn a new technique or learn a new river. So...
Pay attention to everything the guide does. Some guides keep up a constant patter about what they're doing, but most don't. Ask questions.
Example:
Guide: Put the plugs out 40 feet.
(client does so, then...)
Client: Why 40 feet? Is that a general rule, or does it fit this spot particularly?
Get answers, that's what you're paying for.
Guides generally will do everything except reel in a fish for you if you want or need. However, what you want to do is do as much by yourself as possible so as to maximize your learning and fishing time. If you hand the rod to the guide everytime you break off a leader or get a backlash, he or she can't row while fixing you up, so down goes the anchor and time is wasted. I'm sure that 90% of the folks on this board know how to rig a rod and bait up. If you do, then do it. If you don't, then pay attention, ask a few questions, and learn how to do it yourself ASAP. Not only will the guide appreciate it, but you'll get more fishing time.
This is not to be construed as to mean that guides don't always work while out with a client, because they do, but the harder you work to catch a fish, the harder they'll work to hook you up. Basic human nature.
Make your guide feel like he's part of your trip, not just a work horse. Include him in your conversations with your fishing buddy, and include him in pictures of you with your fish. Be polite and courteous. Just like the last example, the more they like you, the harder they'll work to hook you up.
Absolutely DO recommend a good guide to anyone and everyone who wants to know. They get the majority of their business from either repeat customers or word of mouth advertising by pleased customers. If you heard from someone else about your guide, tell him who.
If a guided trip results in no hookups, it is not likely the guide's fault. Don't rip him when you get together with your buddies. Hopefully you paid attention and learned enough to make it worth your while, even if there were no hookups.
If a guide's a jerk, that is his fault and rip him to anyone who will listen. That word of mouth thing works both ways, and guide or not, we all look bad when fishermen act like jerks on the river.
Lastly, if a guide works for a service or resort, or is working for another guide that day, report good guiding directly to the guide's boss. Far too often they only hear the bad things about their guides.
Fish on...
Todd.
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Team Flying Super Ditch Pickle