I personally have a VPS through vultr.com that I pay $5.00/month for. It is running Debian 12.
I have a couple of websites on it, but also have it set up as an OpenVPN server.
I used a script from GitHub to install Openvpn, and it made setup fairly easy:
https://github.com/Nyr/openvpn-install
I just save that script in an easy to remember spot, and run it (as root or sudo) whenever I need to generate a client cert. You would need a cert for your ZM Server, and a cert for your device or laptop or whatever you use to access your ZM server.
All devices will need to have Openvpn installed.
With the above configuration, I can access my home servers via VPN tunnel from my phone, tablet and laptop. I also have a few other web-services running on home-servers (like a plex server) and I use the same OpenVPN tunnel to access all those so I can watch Plex while I am away from home.
ASUS Routers can run a OpenVPN client... and allows you to access your entire home network remotely. Two ASUS routers with OpenVPN client (one at home, one at work, for example) allows you to have your home network and work network merged. I have used this in the past, but now I just have each server at home as its own OpenVpn client