Maybe what you really want is fishing knowledge/experience. Try skimming through "how to fish" books at home. Learn about the seasonal patterns and behaviors of the fish you're after. Then if fishing is the focus of your trip, by all means get a fish finder to show you how deep it is and an idea of the bottom. I don't think equipment catches fish as much as the fisherman's experience does. They also know how to use all the tools better. It's a fun journey to put knowledge together and see it prove out in the field. Plenty of very knowledgeable fishermen here.

There are plenty of rigs that catch fish but don't snag up too easy. Bead chain sinker and a plastic worm rig is cheap and works OK for me. But I'm not too focused on fishing and go at times of the year when the fishing isn't that great.