Hello friends! Do you think an inexpensive GPS, whether hand held or fixed mount offer better or worse accuracy than a more expensive model? Many inexpensive GPS' have less features than a model that costs a few or more than a few dollars more. That difference in price between models can be features such as water resistant or waterproof, internal or external receiving antenna, the ability to easily remote mount an external antenna, size and viewability of the display screen, use of electronic charting chips, color or black and white display just to name a few "features". GPS models are usually purchased according to individual needs and wants. A fixed external antenna is usually the best receiving set up for a boat. One important factor regarding GPS accuracy is satellite geometry. Satellite geometry refers to where the satellites are located relative to each other from the perspective of the GPS receiver. Satellite geometry becomes a factor when using a GPS receiver inside a boat or car, near tall buildings, or in mountainous or canyon areas. When the GPS signals are blocked from several satellites, the relative position of the remaining satellites will determine how accurate the GPS position will be, if there are enough satellites received to have a position determined. Atmospheric and weather effects can also affect accuracy by delaying the propagation (signal speed). How accurate is GPS really? A typical GPS receiver provides 60 to 225 feet accuracy, depending on the satellite geometry and the number of satellites available. This can be improved to fifteen feet or better with the use of DGPS (Differential GPS). DGPS uses a second receiver to compute corrections sent from land base beacons to the GPS measurements. There are many factors which can affect GPS accuracy which are not cost conscience. Use the model which works for best for your vessel and you!