The friend rarely uses the property and came to my parents wanting them to sell the property with him, while the market is high.

I guess you could also do a combination of the two.

Lenders - how can one use combined equity in multiple properties as a down payment without selling or refinancing the individual properties?

These factors combined have contributed to a situation where rents are low for 2/1 units and SFH prices are high for 3/2 or 4/2 houses.The house itself needs some general work, and I am comfortable estimating the costs on that work, but I am not sure what it would cost to turn it back into a SFH.

The landlord was a little old lady who was smarter than all of us combined.

The lowest grade assets consistently underperform usually being a combination of 3 or 4 performing properties and 1 with a bad tenant dragging it all down.   

It's rare that you have a nightmare experience that you might imagine from a frat house.Shoot my a message if you have any specific questions.Again, welcome.Alex

I think I can get $1000-$1150.It’s a rather rare property in this area because it is under $250k in a decent neighborhood and it doesn’t need a lot of repair.

Combine a HML with unsecured lines of credit, preferably in the business. 

There is rarely a step between like this and I would be worried there is a question of side payments in this case.