Soldato
Your house layout looks almost identical to mine (apart from I have a ensuite at the back of the house on the top floor above the kitchen/office side of the house). I was putting down wood flooring in my living room any way so I ran a load of cat 6 around my living room to my under stair cupboard and then was able to get a cable up by the stair case and in to my office. I also ran another cable around my office (did not run from below, perhaps should have done in hindsight) so that I could mount my unifi wifi AP high up. I get really good speeds around the whole house (28-30MB/s over the wifi).
I did not put a network cable up to the top floor but I think I could have done it internally. I did think about running cables to all rooms but I don't think I personally would have ever used it in those rooms so there would be no reward for me.
Note - I have never done this before so it was a learning experience along the way. Including crimping my own cat6 cables and data points.
Downstairs network install:
https://imgur.com/a/O64caQN
Middle floor network install (office only).
https://imgur.com/a/bt5E4j0
I did not put a network cable up to the top floor but I think I could have done it internally. I did think about running cables to all rooms but I don't think I personally would have ever used it in those rooms so there would be no reward for me.
Note - I have never done this before so it was a learning experience along the way. Including crimping my own cat6 cables and data points.
Downstairs network install:
https://imgur.com/a/O64caQN
Middle floor network install (office only).
https://imgur.com/a/bt5E4j0