[KenWittlief]

They took the military dither (encryption) off GPS about 8 years ago.

Commercial units with position accuracy down to a couple feet have been available for a long time now.

and if you want better, there is a local / surveyor mode where one GPS acts as a reference point in an area, allowing you to get position accuracy to less than a inch!

Also, if you are outside there is no reason why your GPS would lose satellite lock, unless you go through a tunnel, or into a heavily wooded area.