I think they both have pros and cons, but what I love about REI is that you actually get to see what you have accomplished, where as stocks and bonds you don't really see the physical accomplishment.That is not to say not to invest in index funds and ETFs, but I think it really depends on your preferences and risk tolerance!

Is this best accomplished as an interest-free loan or as a standard contribution/distribution?

But what I really want to know is what strategy I could use or do to accomplish the goals of everybody without killing them what could I do to get a house at a deep discount from these people that need this relief the most without hurting them and making it worth their while.

There's no need to violate local bylaws to accomplish this.

You can get a lot accomplished through a conversation to find out if your counter will fly, or they're willing to do it with some concession from you (faster closing, renting back after close, etc.), or if they'll reject it flat out and kill the deal.  

Since my wife and I completed our first deal, a live-in flip in north Jacksonville FL, I have become more interested in real estate investing and dedicated to using real estate to accomplish our long term financial goals.

Can you think of somehow to accomplish this? 

You will need to build a power team on the ground where the proeprty is located to accomplish everything that must be done in person such as renovations and project oversight and management.  

If it takes you a day or two to muck about with preapproval stuff, boom that property EITHER already sold to someone else, OR it wasn't actually that great, but either way you aren't accomplishing your goal. 

I'd love to meet up with you, and see if I can't help you accomplish your goals.