Credit Score Requirements for Tenants

[James Free]

I see plenty of posts on the forums where people talk about whether to accept tenants with poor credit or to fudge your own lease criteria for people with weaker credit (don't!). What I don't see as often is a good survey of what credit scores people are requiring for different classes of property and in different regions. 

If you own rentals, what is your region and tenant class, and what credit score requirement do you use to find good tenants?