Earlier quoted context omitted.
For all but the smallest apartment buildings, this is not a good idea. Ethernet has a 100m limit. By the time you go up a wall, back down it, zig and zag around things in the ceiling, etc, you can quickly hit that limit. Then you can start getting errors such as packet loss, crosstalk, etc. Yes, it depends on the size and layout of your building (maybe your building has a comms cabinet on each floor, or wing, etc) bu…
I did technician work as a side job during college. It seemed like most dorms had data closets every floor/every other floor. Some buildings only had them in the attic and basement, but they were also usually limited to 4 levels. Are most large apartment buildings similar?
It wouldn't surprise me if fiber optic cable was cheaper than cat6 to buy in bulk (Copper is expensive, and the process to manufacture the copper cables is more complex), and if you're doing fiber to the building anyway, you still end up with a media converter - so there is likely no significant cost saving there either.
It may actually be higher cost to have a centralised (within the building) media converter - ports need to be provisioned for the max possible customers up front. The class of hardware will likely be different too - matching enterprise style datacenter hardware, instead of the cheap and easy to replace stuff they send to customers...