They could be a criminal or con man.

I think that this would be a good way to cover the fee's associated with the credit check and criminal background check.

I have several different applicants (different families) that are interested in filling out the application and paying the fee of $55 (which covers background/criminal, credit, and eviction reports). 

The same learned set of behaviors that get you through being beaten as a child aren't the ones that get you through a financial crisis.

Criminal background: No violent felonies within the last 7 years.

When the consequences are financial ruin and a potential criminal record, I think that's where I draw the line.

A quasi-criminal?

Especially that they are trying to make landlords responsible for the personal behavior of the tenants!

Regarding tenants, I'd encourage you to spend some time considering what your criteria (credit score, criminal activity, etc) is for a tenant and certainly use some professional tenant screening service to vet them and see that they meet your criteria.

It's amazing what you can find through a simple google search (i.e. maybe criminal charge was removed from the person's record, turns out their Facebook shows they like to party, etc.).