Setup Argo Tunnel on router

Hi there,

I was looking over the internet for a way to expose multiple devices from multiple clients over the internet, behind a firewall, and without static IP, and without unblocking ports.
The idea is to have a way to manage those devices.
The first finding was ngrok link (ngrok - secure introspectable tunnels to localhost) the second was Argo Tunnel. I used Cloudflare in the past so I’d like to give it a try first.
Each customer has RUT950 router (RUT950 - 4G LTE Wi-Fi Dual-SIM Router | Teltonika Networks) so I’d trying to reuse that device to establish tunnels.

Typical use case:
The customer has 4 devices in his local network to which I need access. They all have a web interface, but it is only accessible when I’m inside the local network.
I’d like to expose all of those interfaces via Tunnels.
Ideally, I’d like to be able to access those devices via a web interface,
so I can open device1.client1.mydomain.com, login to that device (in a secure way like shown here: https://blog.cloudflare.com/ssh-raspberry-pi-400-cloudflare-tunnel-auditable-terminal/) and have the same web interface as I would log in from that local network.

My questions:

  1. can I use a single cloudflared client to set up multiple tunnels per client?
  2. do I need multiple tunnels per client at all? Or can I setup one tunnel and use it to access multiple local IP’s?
  3. can I set up a cloudflared client on a single device in the client’s network and access multiple devices in that network?
  4. can I use RUT950 to start cloudflared client? I already have that device in many clients networks, so I’d like to avoid the cost of the extra device at clients place. The devices I want to access don’t provide a way to install anything on them, they are an out-of-the-box devices that only have web interface.

Sorry for all the questions, but I couldn’t find any information on how to set up Argo Tunnel on router and expose multiple services.