There are also 2/3 balconies attached to each floor/unit.The finished basement and 1st floor are open spaces right now with the potential to create 1-bedroom units.

I'm not emotionally attached to the property or anything...

You may even get less than that due to their emotional attachment to the property.

View report I have run the calculations on a multi family property and I need to have someone review the information in the attached report to help me see if this is a good deal. 

There's about $50K in repairs that should be the seller's responsibility, so now we have to decide if we want to ask for that at closing, or if we'd rather not have a retraded deal attached to us, and just bump the renovation budget from $1.34M to $1.39M.

Here they have just as much value as stick built if they are attached to land by themselves. 

The detached garage in the far back would be perfect for an ADU, but how do I determine the ARV of the property if I want to flip it with an ADU attached?

If the numbers work, you can probably have cash in hand in less than 3-weeks.I would be happy to walk you through the process and answer any questions, no strings attached. 

And, the fact that the sold price isn't attached to the deed isn't affected by what may or may not be contained in the MLS.

I did purchase an H house through foreclosure that has a mother in law unit attached.