If you are a small startup and do not have strict regulatory or other special req. run on something simple like DO, Vultr etc. and save yourself pain and $.
https://www.digitalocean.com/community/tutorials/an-introduc...
Public network + firewall feels dirtier than private network, but in reality they are the same thing: a network that’s only accessible to your VMs, to the extent that you trust the provider’s software to enforce that boundary.