D-Link Covr-C1203 may be a solution to whole-of-home Wi-Fi by using three separate Wi-Fi routers that mesh together to provide Wi-Fi coverage up to 465m2 (approximately 20 x 20m2).
But there are so many caveats to the above statement that is it important to understand how mesh routers work.
GadgetGuy wrote a tutorial on Mesh, and you must read it before deciding to go mesh. Think of Mesh Wi-Fi as lots of Lilliputians carrying the load versus the raw grunt of Hercules and his mates. Grunt is good especially if you have a lot of Wi-Fi devices.
It is easy. You can use the D-Link Wi-Fi app for iOS or Android or use a PC/Mac browser.
In both cases, you plug in the main A unit to power and an Ethernet cable to your Gateway. It’s not a modem/router, so you need an internet gateway.
Once done its SSID appears, and you log into that with the default password.