I am looking for a non smart phone for max $50, but I am not sure I get the 2G/3G/4G voice thing. Can I use an old Motorola V3, or how about the Nokia 222? All I want is a calling phone with a large battery that can be used the next 3-5 years.
What phone you can use will depend on the carrier you want to use. Contact the carrier or check their web site and ask what devices specs you need. They likely have basic phones they sell for cheap.