I’m not sure of the legalities of what you want to do & I have no experience with utilities apart from common area services, but herding cats sounds easier than turning the OC into a retail service provider for communications. Locking people into/herding them towards a particular provider is going to be very challenging if that is what you are proposing.
If the gigabit internal building network is to be delivered via building copper I’d be asking for more details & real world examples. Network speeds tend to deteriorate when they leave the lab & marketing materials. 😉
I’d be researching the wholesaler & their performance very carefully & asking questions at a tech. based forum like Whirlpool: https://forums.whirlpool.net.au/
Another path – our OC went through the NBN technology choice area switch program & had NBN fibre pulled to each apartment. We now have a building of very happy residents, tenants & businesses who choose their own service providers. More details here: https://www2.nbnco.com.au/residential/learn/network-technology/technology-choice-program/area-switch.html