: Known for a rigorous verification process, Swappa is a peer-to-peer marketplace where sellers must provide proof that the device is functional and has a clean ESN/IMEI.
For the best variety of conditions (from "for parts" to "factory sealed"), these platforms are the most reliable sources: where to buy used iphone 4s
: Useful for finding refurbished units that often come with "new" shells or replacement batteries. Prices typically range from $30–$55 for refurbished 16GB or 32GB models. : Known for a rigorous verification process, Swappa