Certainly you want to shop around because there is a lot of variation.

Good cash flowing market but you really do have to be careful with the area...lot of variation in crime and neighborhood quality depending on where you look. 

Or a variation along these lines.Your last scenario is right except for the quiet transfer of title. 

A variation of this, if it appeals to you, would be to move out completely if you can live elsewhere cheaper, and rent out the entire place.2) You can pull out some equity from your house through a refi or a HELOC.

For a Monte Carlo simulation, I might apply a +/- to that and see to what extent variations in that estimate have ~non-linear effects on the final answer.Agree that one of the biggest impacts is the current value; for two of my properties the mortgage company provides an equity estimate (which I have no idea how accurate it might be since websites like Zillow, etc typically don't handle multi-family properties very well), but here's a sampling of the estimate variations from different sources:$252K (Appraisal for refinance 21 months ago) vs. $269,939.00 (MortgageCo) vs. $294,900/$321,230.00 (Realtor; CMA vs.

Product sheet on the site.  10,000 loan variations plus a net branch system where you can learn the lending side of things and earn on both sides of the fence, doing your own real estate deals and the ones you don't offering financing. 

I deal with the monstrosity known as the NYC building of department as well as smaller municipalities like in my hometown of Yonkers and there is a wide variation on the time involved and what they require.

They all have it's variations and methodology.

- Most lenders will lend between 65-75% of the resale value, and may offer a variation such as 80-90% of purchase price including or excluding rehab costs up to 100%.

At times there are deed restrictions for 30 days, or for 90 days for more than 120% of purchase price or other potential variations but those are the two most common