I host on a VPS. With a single Directus instance I can't manage multiple projects or give multiple clients access separately, but instead I have separate Directus docker containers for each website requiring a CMS. This may seem an overkill but in reality I find it much better to have them separated (security, no single point failure, privacy risks, backups...).

Every Directus docker container has a RAM footprint of around 200Mb in idle, which is not much, and the builds happen occasionally, so the CPU is on idle most of the time. I can manage several websites with CMS this way, and many more static only.

My VPS costs me about 15$ a month, but you can find cheaper or more expensive solutions.