Deleted Comment
For several years, ngrok was practically free, only recently they've started monetizing once it gained popularity.
On top of that I keep running into unexpected roadblocks with Cloudflare, like when I was trying to set up the tunnel they required me to set up a dedicated domain, you can't set up a subdomain of an existing domain. Probably fine if you are rolling it out as a production service, but for just testing it to make sure it even works (see IPv6 comments above), I just wanted to set it up as a subdomain.