Could I get by with updating a GPS biannually, or even triannually?

If I purchase a Garmin GPS (I'm thinking about getting an Aera 500), do I HAVE to have it updated once a year? If I fail to update it, will it quit working properly? Let's say I skip a year and try to have it updated the next year, will they charge me double to make up for not having it updated the year... show more If I purchase a Garmin GPS (I'm thinking about getting an Aera 500), do I HAVE to have it updated once a year? If I fail to update it, will it quit working properly? Let's say I skip a year and try to have it updated the next year, will they charge me double to make up for not having it updated the year before?
Please note that I don't plan on flying in any IFR minimums; my reason for wanting a GPS is that they are going to be letting the VORs going out of service (the ADS-B law becoming effective in 2020), so I feel less safe doing cross-countrys. I only plan on doing basic VFR navigation, and I mainly need something to point me in the direction of the airport, and to tell me how far I am away from it, that's about it.
7 answers 7