Here is the method I use to nail down my rehab costs:1.

I'd say the key will be to nail down a niche and get started.

My understanding is the asbestos particles could possibly be released if, say a nail was pounded into he wall to hang a picture, or someone cuts into the wall. 

@Nicholas L. nailed it lol it's not the calculator it's the market! 

- You've nailed it.

@wes brandYou got the nail on the head when you said that if they can't afford to carry the loss is not for them...

@Sam SwizzleYou nailed it.

(which I think is what @James Wise is talking about).One thing to keep in mind is that "Poor People" (yes I know, Escalades and nails and etc...) will be happiest (stay longer) in a neighborhood where they have the services they need, such as clinics, liquor stores , pawn  shops, buy here pay here, rent to own--type of shops, vs. higher end things, like Neiman Marcus, where they can't afford to buy anything.              

The market is much cooler there allowing you more room to push negotiations and avoid multiple offers.I currently have 2 under contract in 44310 and will be at 11% cap on one and 10% cap in the other while setting aside 20% for pm, maintenance and vacancy.

Expenses are just under 50% annually with the two units empty.The seller is at about an 8% CAP on the current numbers.