I think the thing to remember is that housing rentals are a customer service business and sometimes you’ll have to spend more time with one building than another.

And remember, CPI of nearly everything is higher every single month, which permeates into materials, services etc… that are necessary for building / renovating homes.

I also learned to keep reserves.

First: Thank you for your service @Sonny Jay!

I don't know if this makes it easier or more complicated, but our upper level may not have any gas services at all (husband is going to the property tomorrow to see if upper water heater is gas or electric, and whether washer/dryer in each unit are gas or electric).

Avg rent with this criteria is $1850+As far as reserves, I am saving about $4k/month, however, these funds were going to go towards my next property so I guess the answer would be no, I do not have separate reserves set aside for big expenses. 

My formula is not complex... something like this:High school rating > 8"(Estimated Rent x 12) - HOA - Prop Tax - Insurance @ 0.3% - Vacancy @ 5% of rent - Debt Service @ 8%" > 0I want to be able to customize the metrics, and find properties I can purchase as an investment.If anyone is an avid user of StockRover and their custom metrics, that is exactly what I am looking for - but for real estate. 

My fourplex is fully managed by a full-services local property manager, so I am 100% passive.Business License department did confirm that I do NOT need a business license because my property is fully managed by a local property manager.

I would want to see as many years budgets as the seller has available and a copy of the most recent reserve study.

Mortgage servicing company is not helpful to find this info.