It's worth looking into the wifi bands and channels you are using. There are two current different wifi frequencies; 2.4Ghz and 5Ghz. 2.4Ghz is the older standard and every device will support 2.4Ghz, 5Ghz is the newer faster frequency and older devices might not support it. Most modern routers will provide both 2.4Ghz and 5Ghz, and will let you run both 2.4Ghz and 5Ghz wifi networks at the same time. 2.4Ghz gets through walls etc better, (lower wavelength = lower attenuation by obstructions), even then 50 meters reduced by 25% for each wall or floor the signal passes through is a decent rule of thumb).
Within those frequencies there are distinct channels which can usually be set on your routers config pages. Broadband providers have a habit of installing every router device on the same channel and when that happens the routers have to wait for each other to talk. 2.4Ghz technically has 11 channels but there is a degree of interplay between them. Channels 1, 6 and 11 are truly independent. Channel 3 would tread a bit on channel 1 and 6. Channel 2 treads more on 1 and less on 6 etc. The 5Ghz bandwidth has more channels and there is no crosstalk between them but it's range is far worse if you have a solidly built house with brick interior walls.
If you are having range issues make sure you are on the 2.4Ghz wifi network and then try logging into your routers web interface and experimenting with channels 1, 6 and 11 to see if you get an improvement. There is no need to change settings on your client devices as they will follow the changes you make on your router. If you have an apple idevice you can download the free "apple airport utility" and use that to scan wifi networks in your area - I can see 4 routers fighting over channel 11 here. I am sharing 6 with one other household and there is only one router on 1. I live on a 50's built estate of semi detached houses with decent sized front and back gardens. It's not exactly high density housing.
I don't do the technical side of networking anymore, but I had a ruddy nightmare with reliable connections when I started working from home.