If you just want a GPS, take a look at the Garmin 421. They can be bought for about $300. The 421 just has basic mapping, but has an SD card slot for better mapping and loading and downloading waypoint. If you need inland lake mapping, let me know what lakes, and I'll check if Garmin covers them. I had a 421 myself, and have map chips for US inland lakes, US coastal waters, and Ontario Canada inland lakes.