Selling the phone / anything I should do before? topic

Got this phone for my gf but she can't stand it since it's not a Samsung :eek::eek::eek:

Anyway, I am selling it on eBay.. is there anything I should do besides a factory reset? I'm not sure if there's a SIM card, or how those work. We're going to reactivate her S3 and buy a S5 retail with the proceeds.