Not all home routers have UPnP enabled by default. So another thing to check, and not just assume. Myself, i just hard code it to trigger instead of auto. The settings might say something like "Port forwarding" depending on your router.
And ya, like he said, if you have a neighborhood NAT you are done unless you can pay your ISP to get out of it. The only other alternative is you get a paid VPN that supports port forwarding, not all do, so check first. We have that here too and burnt me when i moved from cable ( which didn't ) to fiber a few years ago. Sort of caught me by surprise as it was NOT listed in their documentation. I had to call their support to verify "hey, is...." To get out of it, i opted for a business account, as i need incoming connections for other reasons, and didn't feel like screwing with paying for a 2nd service for VPN.