With regard to technology, we consider it reasonable to require (!) From an employee fast Internet (there are fans of ten megabits per second), as well as a headset + webcam (or, as we wrote above - a normal phone). You can pay extra for something (for example, ordering a headset).
Another requirement is a phone. By phone an employee must be available within 10 minutes, exactly as it happens in the office. If you are at work and not in a meeting, you must answer, is that reasonable?
The third requirement is the room. This is obviously not always feasible, but during work people should be isolated from family/children/ dogs and so on. Otherwise, efficiency will tend to zero. If you can't allocate a separate room, you have to explain to your family that working at home is not a leisure activity, but a distraction every five minutes.
Notifications. Here we have come up with this: there are chats (for example, in the telegram text and Skype video), but when a person works, he closes them all (which is correct, otherwise there will be a lot of distractions). If the problem is urgent - we use another messenger, preferably exotic (like Signal), where there are no friends/channels/spam, and where you will be written ONLY on an urgent situation. In all other messengers we mute and work quietly.
The last one. Tracking work. Of course, there are people here, but the work must be controlled: time billing, video control - is not the point, but people must understand that if they are not paid piecework and not by the hours, then during working hours must work.
And what have you introduced for full removal in your companies?