I also once thought about buying cheap keys, but somehow I didn’t dare because of too many reviews that they fly off after updates or after a few months. As a result, I decided to look for alternatives that work locally. One of the options is
kms activator, which does not require purchasing a key and does not connect to any third-party servers. This is not an ideal scenario, but sometimes it’s better to have something proven than a dubious “official” key for $ 3.