Additionally, be sure to have an accurate ledger and your signed lease agreement.

I heard that less than 20% down causes additional insurance fee? 

I read the actual laws on the books in addition to seeking investor input on this site.    

Duplex have different zoning that may permit additional units.

Additionally, the supply of homes for sale is constrained because of this and will be for some time putting upward pressure on prices in most markets.Thinking about renting your house in Seattle would be wise as someone else will pay the mortgage down, and rents and the value of the property will go up over time.

Yes, I still did my own due diligence but PPR saved me hours of additional research.Perhaps the biggest reason I ended up working with PPR is because of the BiggerPockets community validation.

I heard that you would need to get neighborhood approval in addition to the city approval... 

They are all pretty the same this one cash flows the least amount but has some additional upside.   

We look at lenders (so long as they lend in the asset class you are considering) as an additional line of due diligence (they deeply care about their money and they are likely more sophisticated than you are).

They will have additional costs for mailing & online campaigns to get leads.