VEVOR Driveway Lights 4-Pack, Solar Driveway Lights with Switch Button, Solar Deck Lights Waterproof, Wireless Dock Lights 6 LEDs for Path Warning Garden Walkway Sidewalk Steps, LED Bright Blue

we bought the set of 4, and i noticed they seemed to be used (they had washer marks on them and the lens was kind of scratched) I put2 on the driveway to see if they work ok. If not, how would i return them? They do light up when turned on, but, being used, i'm apprehensive about the life span.