Go to Ebay and get the Garmin Echomap 44DV. Best slimline design out there. I have it on my 13' (4m) Center console Yachtsman YS. They cost about $250 new or about $199 used/refurbished/open package. Purchase an additional power cord and AC to 12v power socket/outlet so that you can edit and enter new coordinates without having to sit in the boat connected to power there.
