don’t buy off amazon or ebay or that sketchy looking store at your local mall, the chance of it being fake is pretty high
the only places I trust are major department stores, sephora, ulta, fragrancenet
also testers are perfectly ok, they are the bottles that are meant for being on department store display. if I had to buy from ebay, I would buy testers (no box no cap usually) because fake colognes usually come with box and cap, and they won’t try to fake being a tester because testers make less money.