@Saraheliz41 a single free ISP router is often not up to providing good wifi on multiple floors. While boosters can help they are not always the best solution. Sky sell a new system called Wifi Max which comes with a newhub and up to 3 extenders if they agree you need them but at £7.50ma month isnt cheap. You can buy similar third party systems for less than the cost of the first 18 month contract. I iuse one myself it connects to the Sky hub with its wifi turned off and provides fast wifi on all 3 levels in my home. Loads around but check the one you propose can work with or without the Sky hub.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
