How to set up a WordPress hosting company with auto-provisioning

I want to set up a WordPress hosting company simialr to something offered by WPMU Dev, except that all of my plans will come with Divi pre-installed.

So basically the workflow I want goes something like this:

1. Customer orders one of my WordPress hosting plans on my site and makes payment
2. A WordPress Droplet of the corresponding size to the plan purchased is automatically spun up
3. The wp-admin credentials are automatically sent to the customer

I already know how to accomplish step one. What I need help with is how to automate the creation of new WordPress droplets when the customer checks out.

I know companies like WPMU Dev do this and have read about creating a master snapshot to provision droplets, but am still a bit lost. Unfortuantely but understandably, hosts tend to keep the how they do this close to the vest.

Is there anyone able/willing to guide me on how to set this up? If someone who can prove they have done this before is interested, I may even be willing to pay them to teach me how to do this. I do not want to pay someone to do it for me as I want to learn how to do it.

Thanks in advance!