@Lisa MazzarriI know several title companies in Chicago who perform double closings, and can answer any transactional funding questions you may have.  

Considering they all have the same term of 12-18 months, and a projected net profit of 1.5x equity multiple, (a $1MM project, with a $1.5MM ARV) which would you rather:-Debt securities, secured by the property, monthly returns, typically at a higher rate, no accrued returns or profit sharing; or,-Preferred equity, higher risk, quarterly returns at a lower current rate, with a set accrued return which brings your total returns higher than would be with debt; or,-Common equity, highest risk, quarterly returns similar to preferred equity, profit sharing upon sale or refinancing the property based on your % equity ownership.Also, any additional information you're willing to share would be great such as the type of deals you've invested in and the performance/results of those investments, especially if they influenced your decision.

Is it safe to retire when your net rental income = expenses (seems very risky to me) or when it is 2x, 4x (seems like a reasonable bet), or 10x your expenses?

Is my best bet Hard Money?

They have a performing asset on their books - In my experience, they've always been happy with that.The biggest risk to me of doing subject to is that the original owner gets a home equity loan and splits - but in that case, you're only out the money it took you to catch up the mortgage.

@Wilson Adams, consider making a small bet first.

A seems like the safer bet for long term tenants and the 18 yrs olds might jump around every year. 

Taking an application deposit requires the tenant to perform by a certain date to execute the lease and provide all the funds due for move in.

Performing energy efficiency retrofits of our properties is core to our operating principals, so we try to utilize these programs when available (even if the program is more show than substance).

So, I would really think if this property will really perform as you anticipate before pulling the trigger.