You have to buy into a good building though.Another option for living in is cooperative housing.

In the research I am doing I a bit confused on how Reciprocity and cooperative states work. 

And he will be paid 10%  of the project cost for these services.Now, I can accept to have a cooperation with this PM without this, he offered me these two options, 1. he is a project ( rehab) managers and the he gets 10% and I get bids and cannot speak with contractorsor2.

Here is an excerpt from the National Assoc of Realtors -   The Code of Ethics obligates REALTORS® to be honest with all parties; to present offers and counter-offers quickly and objectively; and to cooperate with other brokers.

Ultimately I have not done anything to prevent the sale of the property and he is allowed full access with my full cooperation until the contract ends.

That said, most tenants don't know this and most will cooperate but if they don't it will not go well for you. 

If you consider the route of buying homes in a MHC your biggest hurdle is going to be finding a cooperative Community owner.

@Justin Cooper I'll take the HML contacts here in MD,  definitely something I want to keep in my back pocket. 

Offer a small incentive to keep unit neat and tidy for the day of the showing- $10 off rent, for example.At the end of all this, you may want to provide  a gift certificate to each tenant thanking them for their cooperation in the sale.

I would like to be able to build a consistent workflow and cooperation with this person.