Digital Ocean, a hosting company, offer a one-click Ghost installation. This is more involved than a managed host like Ghost(Pro) as you run the server and have to set up Ghost yourself. As a trade off for not having someone else manage the server, you pay far less per month.
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Cheaper than most other hosts
Flexible hosting as you control everything
Free to download and install the Ghost software
No limits on members, staff users or page views
Great documentation for anyone who needs assistance
If you haven't run servers before, you may need to ask someone for help
No automatic Ghost updates (though it's quick to do yourself)
Servers start at $5/month, with no limits on members, staff users or page views because you own the server.