I’m running 9 drops for AP’s in my 4200sq ft house and I never want to do it again. I’m using cat6a and even kicking around the users of using shielded cat6a. Mine is fairly straight forward and only in the attic. I would definitely do 6a if I was going into the walls. I would also run a couple single mode fiber runs to each floor.

If you just cut the foil off at the end you will have an unshielded cable and you can wire it like a normal unshielded cable. I’m basically trying to say if you don’t do it perfectly the worst you get is an unshielded cat6a cable.

Omada is decent and cheaper. Unifi is going to be better and more money

Pushed the cable into the attic and took my AP’s. Next owner will just use the isp provided router/modem

That’s literally how you’re supposed to do it. It will be fine

Ethernet rj45 or phone lines rj11? If it’s really Ethernet get a couple access points give them the same ssid and password and be on your way