The formula(s) would look like:Potential Gross Income (PGI)  = full rents + any other income at 100% occupancyminus Vacancy & Collection Losses (8-10%) is typically usedequals your Effective Gross Income (EGI)Then you subtract your operating expenses (taxes, insurance, management & legal fees, repairs, utilities, lawn service, pest control, etc., and a reserve for capex) to get your Net Operating Income (NOI)From your calculated NOI, you can really start digging deep:Subtract your debt service from your NOI to get your cash flowDivide your NOI by the acquisition cost to get your cap rateTake your NOI, add the reserve for capex back in, then subtract your mortgage interest, to get your taxable incomeDivide your NOI by your debt service to get your debt coverage ratio (tells you how many times will your NOI will cover your debt/mortgage payment).

The typical scam is the tell the person they are out of town and to wire money to there attorney to set up a showing.

Typically your responsibility if from the meter to the house, and their responsibility is from the meter back. 

That typically doesn't pan out in a residential zone (or at least not well enough for the headache in my opinion). 

Multi's are typically more expensive than sfr's (single family homes). 

If it's a typical hoa lien it does not survive the sale.

Hi Jeff,I can only speak for my area of the country (Seattle, WA) and what is typical out here, 6%. 

My offers are typically AS-IS, not contingent on financing, and the inspection is purely for information purposes. 

I think everyone here does it a little differently, but I typically have a higher capital expenditure reserve in the beginning (10-20% of rent) until the reserve balance hits a comfortable level. 

As far as incentives go... sounds good but typically the only incentive I need is the check at the end of the job and a phone call when the next one is getting close.