You definitely are allowed to have your own screening criteria, like a credit score of at least 650, no evictions, criminal background, etc.

PMI fees are depending on the size of the down payment and your credit score, from around 0.3 percent to about 1.5 percent of the original loan amount per year.

For example if you have a property in a better neighborhood and that propert is close to a lower end neighborhood then your rentometer score will most likely be lower than real market rent. 

Without a job, I hope you have a good FICO score.

With deadbeat 500 score tenants.

High levels of personal assets; good credit scores; high income to debt ratio; relatively high levels of "skin in the game" (i.e. down payment, personal equity); a property that can be successfully converted to a sale in the case of default. 

I only have a credit score of 630 and Im thinkin that most people want a 25% down payment on an investment property and that would be out of the question for me for the next few years.

You can advise them that maybe their credit score was too low, or you feel they did not meet your criteria in terms of monthly income.

Personally, I'd flip it, and sell it QUICK for a lesser price and do it again...Holding on to something until next spring is a long time to tie your money up and what if the pipes freeze?  

Because a good paying job is the number one thing you can do to dig out of this very deep hole.A couple of missed car payments will not result in scores of 580 and 640.