Would be too far off to assume a a rehab cost of $40k?

You’re financially protected more with more units/doors.Of course more income.Cons of larger multi family are barriers of entry costs to acquire, operate, and experience.

IMHO I think the draw to the Poconos is it's proximity to two monster metropolitan markets and their middle and professional class who may prefer in many cases to tone it down from places like Miami, Hawaii, Vail, or Stowe, and instead have the luxury of a 1.5-2 hour car trip to somewhere where they will save on airfare, get a good deal on their accommodations, and still have loads of fun with their families without having to deal with exorbitant vacation costs and aggravating travel arrangements. 

Closing costs will be less with this route. 

Now a landlord (and architect), I wouldn't build out the space without the second stair since it really is a safety issue/liability (especially in case of a fire) if anything were to happen.Full excerpt of building code below:According to the Chicago building code on egress requirements, the third story above grade plane within a dwelling unit [which in this case is the duplex-up unit], all the following conditions must be met:1.) the building is equipped throughout with an automatic sprinkler system2.) the floor area of the story does not exceed 1600 sq ft3.) the dwelling unit has an exit that discharges directly to the exterior at the level of exit discharge.Your third story attic space is unlikely to exceed 1600 sq ft, but you'll probably find the sprinkler system to be cost-prohibitive.

Which would mean that all of my clients funds go into my bank account and I would pay them their net payout (rent less my Mgmt fee, cleaning fee, maintenance costs, taxes) at the end of the month instead of them paying me my Mgmt fee.

Perhaps their hours got cut or they lost their job.

He asked me for the following-1: Company certificate (for companies only)2: Drivers license/SSN3: Utility bills4: 1-3 months statement of account5: Documents of the property to be used as collateral (if any)6: Provide Loan origination cost for the processing and transfer of your loan funds 7: Bank details for funding (closing)I have their website, but how can I fortify myself so I’m not being scammed.

Do I call someone in the city or this is something I need to fix myself by calling a contractor who works with cutting trees down?

They accept financing so all cash is not necessary and we are asking them to paying for closing costs.