I'm going to go with one of the Pirahnna Max series fish finders from Humminbird for the kayak. Most kayak fishermen are using the Pirahnha Max 160. I think a couple of places in Phoenix had it on sale for $69 which is a pretty good deal considering it's going on a kayak. I was thinking about splurging and getting the Humminbird Pirahnna Max 167i which is the same as the 160 but it has built in GPS and it goes for $129. I dont know if it's worth it though, it's only for the kayak and if there's not any numbers within paddle distance than why even bother? Plus the added cost of the dry box and 12v battery that I have to get to run it, puts the cost upwards of $160 total vs. the same unit without GPS including everything for around $100. Mainly, I just want to know water depth, water temp and what the bottom looks like. I'm still recovering from some health complications and I have a couple of more weeks to decide! Until then, I can only dream of corvina and tight lines! Fish on!