Depending on the area, tax delinquency can be a HUGE quantity of leads.I would still apply other criteria you might apply to for example eviction or out-of-state owners (perhaps a little more lenient).

@Andrew Malina It depends on what your objectives are.

If tenants are a known quantity (meaning the have rented from me for a while, pay rent on time, and are overall good tenants) I will do updates for them, like put in a new ceiling fan.  

Mine is zoned for 2FR and a converted basement, even if it has the right window sizes, number of egresses requires a variance, which requires a public hearing, and with the local homeowners association coming in with its objections.

If you are self managing then quantity (and quality) of units comes more into play.

The main objective is to lock in the low property tax assessment.

I have been contemplating Real Estate Guys Radio, Joe Fairless, Cardone, Michael Blank, or any of the other big names for a conference to attend.My primary objective is to learn from a passionate investor that can also provide a positive shift in mindset similar to RDPD.

They do not want to push top market rents because when tenant hard times come or new product that is better opens up tenants tend to move to the new shiny object especially when paying top market rent.

I would be cautious on using subjective criteria when screening tenants (ie. seems nice) and instead use objective screening criteria, as well as pre-screen all tenants. 

Most applicants would object to allowing you to run their credit before they've even seen the place and decided if they want it, and rightfully so.