How to consolidate multiple accounts?

we have different free accounts that need to consolidate into a paid account 

Yes it is indeed possible by setting up the paid account as main and then setting up the free accounts as sub-user accounts. 

Here is a guide that will help you to set up sub-user accounts and share forms with them: https://www.jotform.com/help/232-How-to-share-forms-with-a-sub-account-user 

If you have any question, please let us know.