After much research and a while on the phone with garmin, this is what I have found.
Several models are capable of what I want, but the 62S seems to fit the best. You can integrate GIS maps using the custom maps function. This would allow you to define property lines, etc on your PC using a GIS map then export it to the GPS. This does require a overlay, which means you will need some point of reference to overlay the GIS map (or any map image in jpg format) onto the custom map program which uses google earth. You would need a road, creek, houses, or something to line up between the 2 maps to be sure you have the correct scale and location. It also is capable of a "birds eye" image for $30/year. This give you a satellite image of an area similiar to google earth. It also has a jack for a remote magnetic antenna and is waterproof.
Looks like this is the way I will go.