Actually, Trimble's focus is not on consumer GPS, it is on machine control (heavy equipment GPS guidance), survey, and build construction. I'm familiar with the machine control hardware through my involvement with a Trimble distributor. The accuracy, especially vertical, achieved through Trimble's machine control is incredible. However, that accuracy is only achieved through the use of a static "base" and mobile (attached to machinery i.e. bulldozer) "rovers".

I do agree that the technology has become much cheaper over the last 10 years, while Trimble's pricing has not fallen at the same rate.