If I were to "partner" with a higher net worth individual, who's only contribution would be bringing their net worth and signature to a deal, does that fly?

You have to check the individual counties around you to see how you pull those records.

This enables me to buy twice as many properties when compared to a traditional 20% down payment. 

It will be up to the individual lenders to let you know.  

My thesis is: for certain individuals interested in buy and hold, it could make more financial sense to use a HELOC for a greater part of your financing strategy, due to tax consequences.So, I'm under contract on an investment property (my 2nd!)

I've been trying to get a handle on market selection, but for me to be able to do it well, as a part-time investor who has a day job (and then some) feels kind of like picking individual stocks to me.

The data (in OpenCalc spreadsheet) is basically just a summation of individual county data.

Hii am just joined BiggerPockets and i would like to introduce myself briefly:I have several years of experience in international real estate investments, both residential and commercial.I own a company that helps individuals and companies to find the best buy to let investments opportunities (to maximise their return, in terms of rental yield and capital appreciation) or even for personal occupation as a main residence or holiday home.I have expertise in several international property markets, mainly in the UK but also in the United States (specially in New York, Los Angeles and Miami) and other overseas locations such Luxembourg, Malta, Dubai, Panama and Monaco.Thanks to my deep knowledge of the international property markets, i am able to find the best opportunities in the UK and overseas, according to my clients requirements and search criteria.Accordinjg to my expertise and skills, I would be happy to provide information and free advice to all the members, so should you need any information regarding international property investments, please do not hesitate to contact me.I look forward to hear from you !

If the landlord continues to rent to the other individual than that would be an arrangement that continues without you.

In December individual signs lease for himself and 3 children for a 3 bed 1 ½ bath.