Generally they will have higher credit scores and hence should be treated differently. 

This may have been specific to our local version of Sec 8.

What exactly does an "app" do that a mobile version of the website cannot?

I always give a reason, and it is a reason that has concrete information and not subjective information like they are filthy. eg higher income applied, higher credit score, etc.

Taking into account things like vacancy factors, higher rental income version multiple incomes, owner/occupy advantages & disadvantages, income and vacancy stability of the renters, maintenance and land lording issues, etc... and even 2 unit versus 3 unit versus 4 unit properties?

For example, if your looking to manage young professionals with upper 600 credit scores +, don't buy in Joliet.

I have a low credit score due to credit card debt that I am actively paying off.

Being unsecured makes it a positive addition to your types of credit (part of the score calculation in most models).

You still need a good credit score and good personal financial statement, but they won't do a DTI based on everything you have going on. 

I screened the tenants, and have middle income high credit score parents as co-signers.