For every subscription to a hosted Mac running macOS, we provide an adminstrator account and the ability to modify system-level files. Login as administrator to a Mac running macOS and you have complete control over the system.
SSH and VNC access are enabled by default on dedicated servers so you can access them from any device. It's no different than if the server were on your local network.
We do require that you follow the guidelines set in our Terms of Service and Acceptable Use Policy which you must agree to during checkout.