You would gain access to their forms, policies and procedures, and much more.

Select your partners wisely - Realtor, Lender, 203k Consultant, and ContractorREALTOR - it's recommended to work with one that has done a 203k in the past so they know what verbiage HUD wants to be added to the purchase offer contract and how to structure the deal.Lender - advise you to select a lender with verified 203k experience; the lender is the quarterback in the process, controlling the rules, paperwork, processes, procedures, and if the lender does not have sufficient experience with the 203k, your entire process can look like the Cleveland Browns on a Sunday afternoon.203k Consultant - The 203k Consultant determines the scope of work and pricing for the project and inspects the completed work; the lender is responsible for selecting the 203k Consultant (refer to Lender paragraph above).

Depending on how you set up that initial agreement you may have additional procedures that should have been followed to legally regain possession. 

If they can not or will not provide that I would let them know you will be going to the state real estate commission to file a complaint if they do not make things correct.Next I would be careful starting a business that is so litigious and process / procedure driven just because you have a bad business relationship.

If an eviction moratorium is in effect, that doesn't preclude you from filing the appropriate notices and following the proper procedures to get all the way to the doorstep of eviction. 

Each State has their own specific legal procedure that is followed for a property tax lien certificate to be converted into a deed.  

They my not agree but I always use a agent to buy property because the seller always pays the comish.If an agent helps you find a good deal not on the MLS then he/she can always try and find your next dealYou can Google or You Tube next procedure

It would include the listing with 120 5 star reviews and processes/procedures already in place (housekeeper and maintenance folks all in place).

My CPA is willing to try to help getting it set up but is researching the procedures.

You need to evict them via the legal route and make sure you follow every procedure exactly to the letter of the law. ie, when you post a pay/quit notice, make sure it's delivered by an acceptable method as laid out in state/local regulations.