People need to remember that not everyone is filling in a spreadsheet with the most stringent numbers, there are lifestyle advantages to be considered as well.

Good tenants can significantly reduce vacancy rates, turnover costs, and maintenance expenses.Many property managers I know are quick to fill vacancies, often asking, "Do they meet the minimum requirements?"

If you budget the negative cash flow over the course of the hold period and have reserves set aside to fill the gap, there is no problem (assuming your investment meets your target appreciation rates - I understand there is no guarantee there). 

They do so well especially when they need to fill vacancies too. 

Can you mix and match tenants to fill a larger space?

But we moved out the low rent tenants and after the rehab we filled all units with market rent tenants.

As long as your primary residence on your drivers license is updated correctly and you fill out this new residence as primary application, it may be no problem.

Quote from @Adam Bartomeo: A tenant that pays their balance after they move out is almost like spotting a unicorn, bigfoot, or finding a pot of gold at the end of a rainbow.

Buy in the winter, and you'll pay less money for the property, but have to deal with longer vacancy.Buy in the Spring and you'll pay a lot more money for the property, but you can fill a vacancy much quicker.Pick your poison.

These books are filled with practical advice to help you avoid these mistakes that start small and snowball into major issues.