Project Archive Best Practices

We receive and process a large amount of testing requests each week, each having unique requirements and most have a separate SpiraTeam project number.  I would like to implement a strategy for archiving these projects, yet still maintaining access to previous Artifacts (Docs, Test Cases, Incidents, etc.) for reuse and reporting purposes.  I want to get the projects off the active project list, if possible, but still get to the data if needed.  We are on a SAAS Hosted system, so setting up a separate site as a project archive is not an option for us.  What best practice strategy does Inflectra suggest for Project Archiving purposes?  Thanks for any help on this.