I've had lots of success accessing my iMac at home using the Apple Screen Sharing app and connecting to it using Zero Tier. As it's a direct connection there no confirmation needed, i.e., if you connect via Messages.
I have no affilation with Zero Tier. I just like it alot as it solves many problems with remote connections, e.g., same subnet, NAT transversal, etc.
Zero Tier is a 'virtual switch' that creates private encrypted networks which also deals well with getting through routers with NAT/firewall; no manual port forwarding required. If you're behind a home/domestic router (rather than a corporate firewall) there's a high probably it'll work for you.
The basic setup involves:
Once the machines are authorised they are assigned an IP address in one of the reserved private ranges, e.g.
10.63.28.188. You can choose a range that does not conflict with anything you may be using already. The private IP is then used to connect to the other machine.
On the destination machine, make sure Screen Sharing is enabled in the Sharing panel
System Preferences > Sharing > Screen Sharing
Alternatively: Enable Screen Sharing via SSH: How to enable OS X screen sharing (VNC) through SSH?
Connect via Finder
With Zero Tier the machines are on the same private network so the destination machine should appear in Finder, you can then click on it and press the Share Screen button to connect.
Open the Apple Screen Sharing app then enter the private IP address of the destination machine:
Click Connect then you'll be prompted for the login credentials of the destination machine if it has sussessfully made the connection, and once authenticated you'll be presented with the destination machine desktop.
I hope this helps someone!