I have a Garmin Etrex. It is a very basic GPS receiver. The electronics are waterproofed but the battery compartment is not. I have dunked mine before and shook the water out and continued on my way.
I can enter coordinates of points of interest by lat/long or other coordinate systems if I desire. Then when I arrive at the put in, I can have the Etrex point the way to the desired waypoint. It will do anything I need it to do. If I am paddling confusing unfamiliar back waters, i mark and lable waypoints on the way in, or I can follow my track back out if I want. It has come in quite handy on a number of occasions. Once when the fog set in, I would have been in there till it lifted. I have seen more expensive and full featured units that I would appreciate. I especially would like the overlay maps so that you can see more of what you have around you. On the etrex, the only thing you see is your track and things you enter. But as with all things, you get what you pay for. The Etrex works well enough that I will not get another unit till this one fails, but when it does, I will upgrade. I have seen the Etrex for sale at $88 as it has been discontinued, but they have similar bottom line units. that is a very fair price for the unit.
https://buy.garmin.com/shop/shop.do?pID=6403