How to "install third party software.." and "budgie-extras" via bash

If one has not selected “install 3rd party software…” during initial setup, and also wants “budgie-extras” (can be selected via Welcome), are there built in commands to trigger this? I would like to add it to a post install script.

Similar question for the Disks utility (it’s actually a great utility!), is there a way to manipulate its settings for automount?