Satellite host system requirements

Looking at the System Requirements for a Satellite host, I don't see any assumptions for what those are based on/how much it scales with the size of the environment you want to manage.

I'm planning for a fairly small deployment and trying to decide on a cloud VM instance size to use. If there are only 10-20 machines to manage and I will be using an external postgres server, what would be the expected system requirements to handle that operation? Disk storage and RAM are probably the most important considerations.

Thanks!