There are many options for remotely accessing Home Assistant:
-
If you set up DHCP reservation for the Surf Soho on the TP Link router, I believe you can then use it to configure OpenVPN the WAN interface and IP addresses on the Surf Soho. Then you can establish an OpenVPN connection to the Surf Soho. Note: You can also configure Dynamic DNS on the Surf Soho to get a Public IP address which would allow you to reference the Surf Soho wherever your Surf Soho is connected to the internet. There are free DDNS services available.
Configure Remote User Access using OpenVPN -
You can go to the Tailscale web site for configuration help. There is also a Tailscale reddit site where you can get help. Your configuration should be pretty simple. You may want to consider defining an Exit node in your home for situations when you want to use the IP address of your home internet to connect to something like your bank accounts.
-
Home Assistant can also be configured to be remotely accessed through the Home Assistant Cloud for a monthly/yearly fee.
https://www.nabucasa.com/