A basic model at a little over �100 would probably suit Geocaching. However to really get the benefit of a GPS you want a more advanced one that you can load maps onto as the basic maps that come with GPS are very basic. I have a Magellan Meridian GPS. The basic version was �200 and can load maps for travelling. They are quite expensive at around �100 each, however, you do get all of Europe or the States. I took mine to Florida with me this year and the accuracy was quite amazing. The only downside is you generally need an additional memory card to hold the maps although these are only �20-�30. As an example a single map upload to the Meriadian at 16mb covers all of Scotland and North England. 3 x 16mb chunks will cover all of Florida. On holiday instead of the kids asking how long it would take to get to the destination they just watched the GPS counting down the miles. Peace and quiet. Almost worth it for that alone!