Just with back-of-the-napkin guesstimates and $2,450/month gross rent, I'm seeing the Cap between 5 and 6%.

On our introductory phone call he did a napkin analysis of my portfolio and got me thinking a lot about what I am doing and how to improve it.

In my area there are some that seem like they keep track of rentals on napkins.

Personally, I like to run every deal through an easy back-of-the-napkin test before even pulling up an actual underwriting model. 

You may find in this environment you will be asked for 30%, 20 year, higher rate, which makes this deal look worse.If you pay cash....quick napkin math assuming 50% of NOI for expenses that leaves you with ~$70k which is a 3% return. 

We subscribe to a market research platform called Yardi which only provides information on multifamily properties 50 units and larger so if you are invested in a property that is 50 units or more, I would happy to provide quick "back of the napkin" valuation and methodology.

Unlikely.80% of our landlords use Excel or bar napkins or some combo. 60% of our small business owners are single-shingle "one man bands," and they too use Excel.QBO, Waveapps, Freshbooks, Stalebooks, SloppyBooks, Xero, One and all the others are nice to have but not must haves until you have several rentals or complex rentals (such as a strip mall or something).

The County Health Department (I think) could use the house address to confirm to you if one is allowed or not.I've worked with Citizens for potable/drinking water, but not sewer.Could you help me understand if you're talking about storm water (rain water) or sanitary sewer?

@Dany JarjouraI do 2 minute “back of the napkin” math on potential properties.

Practice it enough and you'll learn how to analyze property on a napkin or in your head.Remember: the math never changes.