How to make demo wordpress websites easily

I’ve created a plugin and am receiving requests for a demo. Each demo contains sensitive info to the customer so I can’t just create a generic demo for all to view.

Currently I create a new sub domain, install wordpress, install my demo theme, import the pages for the demo, install my plugin, activate my plugin and then release the demo to the customer. I then have to go in and delete the sub domain once they have finished testing out my plugin.

I’m sure there is an easier way, could I use multisite for example and create a script that creates a new multisite with my demo theme and plugins activated automatically?

Are there any plugins available that would do this for me? I noticed some theme websites that have a ‘create your demo website, this will be available for 7 days’ etc which is what I’d like to do.

Thanks for any advice