Standing up a QA environment within Prod Cloud Environment

Valued Contributor II

I have a tendency to not see the forrest through the trees, so I figured I would ask here to see how others have handled this.

We have a cloud instance running for production. We are now expanding that cloud instance to encompass the rest of the company. However we want to establish "QA" environment as well and exclude the QA from policies/installs from Prod.

I thought about doing sites, but that seems like it's going to requiring going back and redoing the whole architecture which could/would affect the prod environment negatively and complicate the future state of the environment. Though I could be wrong, I've had minimal experience with Sites, and the gist I got from the forums was avoid sites at all costs.

Currently we have no sites setup. We do have some flag file (dummy receipts) to help differentiate things for config profiles/smart groups.

How would we best proceed from this point to accomplish our need? Re-architecting for sites? continue with dummy receipts and smart groups? other options?