I have a
Garmin 48 and a 12(backup)that have worked perfect. The 48 interfaces with my laptop for chartplotting and realtime navigation.
Garmin does not offer either two but, I have seen them on EBay for as little as 75.00. Any hand unit will do everything you will need, the new ones with map data are good for on land.
If you are looking for a portable
chartplotter, Practical Sailor did not think to highly of the new ones, as they felt they were overpriced for little chartplotting capabilities. Just my opinion?