Talking about these guys: https://nextcloud.com/?
I guess they're providing a free tier but you can request a quote if you need more. It's what I could understand from their site. 

 They have an Enterprise version of the software they sell that has some extra features including 24/7 support lines and whatnot. I know the company sells different types of NextCloud servers/hardware boxes for a few hundred bucks each also. I remember there was also an opt-in paid version for small businesses or power users who wanted support, or to use NextCloud's own servers for backups/storage, IIRC.

Awesome product suite though, I have nothing bad to say about NextCloud. They definitely have some offers that bring revenue though, not everyone wants the full self-hosted experience. 

 It’s running in minutes on my server and phone. Nice software