Questions for those of you who have GPS.?

No fees (normally).

If this is for a driving navigation GPS then some will come with free map updates, others will charge for them. Map updates are entirely optional, you don't ever need them. They are however the sort of thing it's useful to get every 3-5 years so that the location of things like gas stations remains up to date.

Some also offer live traffic information, that is done via a cellphone link and may require a subscription/monthly fee in order to work.

Of the few units I've used personally I prefer tomtoms, I find their systems give more useful directions (e.g. the name of the freeway exit rather than the number) than the others I've tried. But they are all fairly similar these days.

The GPS part of any consumer GPS receiver, is free to use, for the 10M resolution provided.

Most standalone GPS navigation systems are free to just plug in and use, but you pay for occasional map updates as you want them (they are made available 4 times a year, tops), and may be able to subscribe to a live traffic feed. Some units offer Lifetime maps and/or traffic.

Network based GPS systems will require subscription at least to a mobile network service.

I would just stick to the big three, Garmin, Magellan, and TomTom.

Im not sure about the models but i do know that almost all GPS systems work indefinitely once you buy them because they already have the maps programmed into them.