Using REST APIs to extend your scripts is a useful feature to implement. You can gain access to new functionalities, and the possibilities to create new more advanced scripts expand.
Most of us have done it—deployed temporary VMs to Azure. Something that many of us also have done is to forget to remove resources attached to those VMs when deleting them. This can lead to unwanted costs upwards to thousands of dollars if you’re not careful.
If you want to run a server in a private subnet, you’ll need to use a VPN to connect to it. AWS VPN is a managed OpenVPN service that can handle this for you, and allow you to lock down public access to your protected instances.