I imagine all those "details" also determine whether or not it qualifies for a short sale, or am I way off base with that assumption?

Invalid assumption...these properties will not have similar returns.Many investors would rather have fewer properties and more units for direct investing and more properties (which means fewer ownership units per property) for passive investing, but this is unrelated to your question.

I analysed my two (2) first properties last evening, with some assumptions made about rehabs amounts and condition of the property. 

This makes me much more comfortable and confident when making assumptions (i.e. rent prices).  

@Chris Martin be careful with assumptions.

This is working on the assumption that you are using your HELOC to use towards the downpayment and you are using the loan to purchase and renovate the home.  

But most of the assumptions on your hypothesis is incorrect:- no way this property sells for $400K.

My assumption is seller financing will give him and dependents long-term monthly income, but not the large influx of capital (and taxes) that would also impact nursing home costs.Obviously we'll need to get a real estate lawyer / tax expert involved but at this point looking for any suggestions or things to consider as we finalize terms.

, I get a 6.5% cap rate, 1.34 debt service coverage ratio and 22% cash on cash - with the assumption that you'll need to spend $10,000 on roof and other repairs in the 1st year.

This is just an assumption of course, so if you are not then my apologies.