I would love to hear from other more experienced in the field about alternative ways to financing that I should consider besides the HELOC, maybe also hear from investors on how the process of bringing investors onboard works.

And the PMs and realtors I know don't want to talk to a website.

One thing you might think of doing is having and promoting your own website to avoid the exhorbitant fees charged by the third party sites such as Expedia, Booking.com and Air BnB.  

I get paid when the deal closes and so should any other lender.

Quote from @Sunil Ghosal: Most of the Boostly websites I see are very slow to give quotes and have higher downtime.

On-line Auction Foreclosure Website.

Aloha Mark,   we've been doing this for years using various software packages like Propstream and others.   

You can allocate those proceeds any way you want - as equal down payments or buy one for cash and others with loans - It doesn't matter a bit as long as you use all of the cash and purchase at least as much as you sell. 

According to what I have read straight from the IRS website and other places, we need to either meet 500 hours, or at least 100 hours and also work more than anyone else on the property.

I believe furnished finder is the way to go as it seems like the majority are looking on that website.