One of the properties is occupied however, I have been unsuccessful at obtaining the name of the current occupants/residents.  

Here are a couple risks you need to mitigate:- Short sales could take a long time or not happen at all- REOs are sold as-is- No sellers disclosures- Some REOs are occupied which means there are no inspections allowed and you may have to evict the occupants - You will be competing with other cash buyers on the MLS

If one of those properties starts to become low in occupancy and can no longer service it's debt, can you borrow from the other LLCs that are within the fund to pay for the struggling asset?

Reserve Requirements 3-4 Unit owner occupied properties must have 3 months PITIThree (3)- and Four (4)-Unit PropertyThe maximum mortgage amount for the three (3) - and four (4)-unit properties is limited, so that the ratio of the monthly mortgage payment, divided by the monthly net rental income does not exceed 100%, regardless of the occupancy status.

In my current occupation, I'm used to digging for and collecting as much data as possible before making an investment decision.

When we took over, all the units were occupied, but we soon discovered that occupancy rate and positive cash flow are not necessarily related.

I would like to close on my first property by June, so I will be on the school schedule with leases, and the one year owner occupant requirement.  

You have to be an owner/occupant renting out bedrooms or an "ohana" in your back yard. 

Well, once FHA realizes you are not an owner occupant, in addition to violating the due on sale clause, I'd expect the, to call it.  

This tends to be more of an issue here for owner occupant buyers than investors, but could affect either I suppose.