Does anyone have a fish finder ? Such as humming bird 160, eagle cuda 300 or garmin 90 ? They are all about the same price $80-$100. I'm looking for something cheap. That works well too. I have a crawdad jon boat that runs on a electric motor. Would I need another battery or can I run the motor & fish find on the same battery? Just lookin for the basic set up for a little cash.