The other problem I foresee is you will not be able to release individual properties form the portfolio.

The water was so bad they had to drill holes in the ceiling to release the water.

agree with Andrew, and also sometimes you're just out of our Earnest money and walk away, but typically ,you if enough info found, you could do mutual release with no issue. 

The "locked in" time would be a contingency period, you typically have 5-17 days to do an inspection (due diligence period) to get the title info, disclosures, inspection (any inspection done), and then release that contingency.

I heard they were releasing some of their single-family home purchases in the Phoenix area but I don't know if this was small profit-taking to balance the books or a sizeable release of homes back onto the market. 

They changed the deal, no go.2) hold back a significant chunk of closing money in escrow, to be used for any legal costs /non payment of rent, cash for keys etc. released only when tenant is out.

The busy-body actions make people think they're doing a bunch of clever stuff and getting things done but in reality not so much. 

The top level questions to ask typically pertain to the operator's experience, their skin in the game, and how they're paid in the deals they do.The Hands-Off Investor by @Brian Burke was recently released by BiggerPockets, that is a good place to start.

Any body *

When it comes time to re-lease, raise rents by $50 across the board and you've more or less made up your difference. 50 dollars shouldn't turn away anyone that was already planning to re-up their lease.