Double NAT with apartment connection

If you don't have access to the apartment complex router, then there's nothing you can do on your router that will help.  The complex router is going to block any unsolicited incoming connections to your server.

One option is to subscribe to a VPN provider.  This sets up a tunnel between your home network and the VPN provider.  This will bypass NAT on the complex router.  If the VPN provider doesn't give you a dedicated IP address, then you may need a provider that offers remote port forwarding.