At my previous company, we went off of pictures from the turn before they moved in. If someone had lived in the apartment for 5 years and they moved out and it was nasty, whatever we replace it. But if we replace the carpet, hand it over and they move out a year later and it’s wrecked, that’s on them. Also if at any point there’s excessive damage from pets that it needs to be replaced, regardless of age. They tend to get replaced every 5-8 years anyway.