We live in an old farm house, with brick walls. When we were doing some renovations about 10 years ago, I managed to run ethernet to most of the rooms. This works if you have a desktop computer and don't mind having it plugged into an ethernet socket. However, almost all the family exclusively use devices that connect via WiFi. We got round the WiFi coverage problem by installing routers in several parts of the house, with separate SSID's. However, there are several parts of the house with poor coverage and you have to remember to connect to the SSID that gives you the best coverage.
Enter the concept of mesh networks. There are several different companies making mesh networks. The main reasons I chose Google are it's trivially easy to configure and the app offers all sorts of performance monitoring. Like other mesh networks you have a single SSID and the network automatically connects you to the unit with the best performance in your location.
Initial setup involves trying out where the WiFi units should be placed. This is where the app really shines. Not only does it tell you what the signal strength is in any room, but you can see the upload and download speed for each connected device. This makes it easy to move the access points around to give optimal performance for everyone.
You can configure the network priority for each connected device to make sure your children don't hog all the available bandwidth. You can setup groups of devices, where you can control access to the network for the group. Useful to turn off Internet access at bed time.
If you need to twiddle with various advanced network settings such as DNS servers and port forwarding, you can do this via the app.
In summary: it just works out of the box, performance is good and it offers lots of twiddling options if you need them.