I ise 3rd party sites like zillow most of the time 

Are you putting it under contract and marketing it or bringing 2 parties together for a profit?  

For example I know in many “flips” an investor invests 100% of the money and the other party manages/completes the rehab and then each party splits the profit.

I used to live on 2nd St and have a couple 4 unit properties on that street and I can tell you that currently in that one-way section it's a 50 mph highway that often times will have some drag racing between lights. 

If you have not met or worked with them before, I would consider at least checking the place out in person (plane ticket is a lot cheaper than some crazy headaches) or making sure you have thrid party inspector and a lot of videos.

With a requirement that all this documentation be reviewed by a third party, adding to the costs of the project.

People often use the term Foreclosure in a very generic sense when referring to a property for sale.REO stands for Real Estate Owned.

Every one of these transactions you generate through marketing should eventually lead to one or two more through referrals and just general exposure to your market, and that part is largely free of charge. 

I like the idea of 2 bedrooms, but as things stand I would need to cut egress windows into the basement.

No gimmick, no needing to pay a 3rd party to manage this, no trickery involving the notion that there are 4 weeks in a month (there aren't) and some mystical magic about biweekly payments.