ive never purchased from craigslist, but have bought these kind of lights from ebay. if they have 50 of these lights, then im sure they came from a wharehouse that was was upgrading the lights and the owner or contractor is selling the old lights. if any questions are asked, just say you have a friend or someone that has a truck garage with like a 20' or higher ceiling and need to either add or replace a couple of these lights. if the lights are being shipped to you, ask if they can tested them before shipping them. if your picking them up, tell them you want to plug them in to test before you purchase. when you plug them in, leave them plugged in for about 15 minutes to make sure it stays on. if you have a new bulb to bring with you, bring it just in case the light goes on and off a couple times during the 15 minute test. usually if the light goes on and off, its a bulb problem, but could be a ballast problem. so that why i would bring a known good bulb with me for testing purposes.
if you cant test where you are buying them, ask that when you get home and test them, and if 1 doesnt work if you can bring it back and swap for another one. if its an electrical contractor selling them, i would hope he tests them all before selling them. i would.
