@Nathan Arnold,It's VERY easy to form a LLC, literately in VA I think it took about 30 minutes online, and $110, but then you also have to get your EIN with the IRS.   

I have red that: class action lawsuit, it is difficult to form a class to receive certification with less than 20 members.

Turnkeys put the control button in your hand.I picked Turnkeys in Phoenix instead of Syndications simply because I like to control my destiny (or as much of it as I can get away with) and for me the numbers in reality, have worked out far better than the Pro Formas I saw for the Syndications I analyzed. 

Let’s go with you have realistic pro forma that performs as advertised (but if you do, they would be the first zero appreciation market realistic pro forma I have seen that depicts this amount of cash flow).Now let’s play this out.  

They are also being sold on pro forma cap rates quite a bit.

While they can jointly form a LLC, there is considerable debate as to whether they can then add capital to the LLC once it is formed. 

For example, if my brother and I wanted to do another property WITHOUT our father, we would need to form a NEW LLC just between the two of us.

I cant speak for MA.

Always keen to meet people and form a community locally as this site is at this stage essentially all American. 

As I understand it, all I would need to do is find an experience F & F to partner up with, form a new LLC for the project, and then go get it done.