Hey Denny - For rehab costs, a good place to start is breaking things down room by room and getting rough estimates for common repairs like the roof, HVAC, kitchen, light cosmetics, etc.

🔒Let's break this down:Under IRC §469, rental real estate activities are considered "passive" by default.

I would definitely go directly into the police department or try to get a call to make a report directly. 

Are you both friends and have unique skill sets and are breaking up the duties of investing based on those skills?

Let's break down a realistic timeline for building your REI business without burning out or risking your day job.  

Hi BiggerPockets Community,I’m looking for advice on breaking even or generating positive cash flow with my studio condo in Prospect Heights, NYC.

I found it an enjoyable read about his journey into notes, but out of roughly ~180 pages only the last ~40 discuss notes and even those are very general and don't go into any number crunching. 

Purchased a little too high at the buy (I knew it at the time too), does a little better than breaking even on cashflow, and took too long to rehab.

This would help you get going.You might be able to make these a  little nicer and force appreciation and a little higher rent.Either way rents will go up over time and the mortgage with remain constant.Maybe even make one unit a STR which could see higher income.I'd be ok with break even or a little bit negative on a Quad given you have 4 properties in one.If you're only breaking even you still have depreciation and other tax write off to help you out.I usually make people 3 offers.

Not that I'm a proponent of borrowing just for a tax break, but the interest is a deductible expense.