Normally I would disagree with you, but it's running fine on my $5/month droplet. So... I'm saving $24/month because I know how to type "npm install."
What do you mean? I don't see anything on their site about being able to self-host it.
I think the parent comment is referring to the open source code which you can self-host for free. You just need to pay for the metal/cloud that runs it.