My wife has recently put in several offers for clients looking for MF in Phoenix and there is a lot of competition to get properties, cap rates are compressed right now.

As part of my research/practice I've been using the method described in The ABCs of Real Estate Investing (great book BTW) to determine prices using the formula Purchase Price=NOI/Cap Rate.

Right now retail strip centers is what I am seeing for value add and stabilized at higher cap rates.Multifamily is tapped out for the most part.

But yeah i didn't even think of the vacancy and the cap exp.

For example initially during due diligence, the HOA rules/covenants allow rental without any cap. so investor happily purchase it as a rental property. 

We also had a bunch of assessments which really hammered the cap rates.

Based on your numbers and a 5% vacancy factor + $2,000 for maintenance and capital expenses  + $2,882 for management I get NOI of $11,882 or over a 9 cap on a $130,000 buy price. 

I've used simplified spreadsheets over the years and have altered them after finding and understanding things like cap rate, GRM, and a plethora of other RE goodies.Two years ago I realized I needed an income producing strategy for retirement.

I'm not sure how you calculated the Cap rate, but it's not 26%.  

Since there is so little that needs to be supplied, I would be very happy to cap off the circuits to the basement and hallway and the front porch light, and simply put in motion detector battery operated lighting in these areas, and tell the tenant to use the hookups in her kitchen, and get out of the basement.