Re: New boater with Electronics questions...
I think most would agree with JB and he has good points. I on the other hand am still useing a 1981 depthfinder and have not updated because the newer units do not have many of the features of the older units.
When they changed to the menu driver units it was better for most because you really do not even need the book but at the Same time they took away my favorite feature.
Also which fish finder is right for you depends so much on how you will use it.
How deep you will fish, Salt water or fresh water, Do you need to see down rigger ball and lures, do you want color, ect.
In General fishing fresh water less that 50 feet you can use almost any fish finder with a 200khz transducer. Get a screen size of your desire but your next unit will likely be bigger.
When you get into deeper water and salt water then you need more power. Down to 200 feet a 200kh transducer is still all you need but get at least 400 watts RMS power.
Salt water over 200 feet then should get a dual frequency unit with at least 500 watts RMS. Also to see small fish you need a higher resoultion.
also if you want to see downrigger ball in shallow water also should get a dual frequency unit as the cone angle on the 50 khz transducer is much wider than on the 200khz unit.
I do agree With JB on the GPS. Get a power cord or rechargable batteries and a 12 volt charger. The GPS will give you your most accurate speed over ground, not water speed. Many units have Water surface temperature built into the transducer.
For shallow water look at the Eagle line, as you go deeper look at the Lowrance line or Garmin and over 400 feet of salt water Furuno is the best.
Take your time, write down the features you want, the depth you need and fresh water water or salt water and then can pick a unit right for you.