Ghost is a free open-source CMS. They have native memberships with 0% commissions and send posts by email.
Ghost (Pro) is the official managed hosting provided by The Ghost Foundation. Their plans start at $9/ month for up to 500 subscribers. Also, you self-host Ghost on your server because it is open-source.
How much are you paying for Ghost?
I pay $15/ month for managed hosting. This way, I don't have to worry about updates and any technical configuration.
Ghost is open source, so I pay nothing to install it. I run various Ghost installations on Digital Ocean droplets at $5/month.