Me & my wife are now both working from home, I have been working from home since March & set up an office in small front bedroom, using the wi-fi from living room. My wife has been home a month and her office is in the back bedroom, but her connection is very very slow and not responsive a lot of times. I did a wi-fi test in the bedroom and it said it was good, but her tech people at work said it isn't, something needs sorting as it is very slow. I'm using this community as not been able to get advisors due to covid.
If you remove all the internal walls, water, electronic and electrical devices, metallic pipes and conduits and wrap the whole building in a thick lead shield you will have a good chance of getting decent Wi-Fi from an ISP Hub.
Just a few things that can affect Wi-Fi in the average home …
Mirrors, furniture, fish tanks, people, radiators, walls (some more than others), cordless phones, baby monitors, microwave ovens, fridges & freezers, TVs, next doors Wi-Fi and Wi-Fi equipment, DAB transmitters, the list is endless.
Many people have accepted that the VM Wi-Fi is poor and have purchased third party equipment that is much, much more powerful than the VM supplied kit and once set up have wondered why they waited for so long.