One of the first things to consider is how are you going to use the handheld gps. You should decide if your handheld gps is going to be used on water, land or both. So that you will have the right maps, charts, mounts and the ability to swap. A handheld gps affords you the luxury of using in a car, in a boat, on an airplane or as a companion on a walk. The next thing to consider is what size and type display does your handheld gps employ. As far as size bigger is always better but, bigger size makes for a larger and sometimes heavier unit. The type of display also relates to the visibility in the sun or in the dark. What maps come loaded with your handheld gps and can you load other maps in the future. An accessory for your handheld gps means more than a nice case. What cable does your handheld gps need to connect to your computer? Do you need an extra antenna for your handheld gps? Another considerations should be do you want the altitude or other weather info. Maybe instead of a gps, do you want a virtual running partner or do you need a Pocket PC?
Now that you know what features you want for your handheld gps the only thing left is to find the Garmin model that fits your personal needs. If you have any Questions use the contact us page. I might know all the answers but I know where to go to get the answer.