Screening tenants I use National Tenant Network (NTN). 

Either locally or nationally.

As a chapter member of the National Real Estate Investor Association we also offer access to travel, insurance, landlord resources, software services for investors.  

Home ownership is at an all time low but national home buying averages is actually increasing.

@Fareed Zahid there are some opportunities to partner with proven, high volume, real estate investors in markets across the nation.

Or any QI with a national presence would also be able to help you out.  

I am trying to look in la mesa, El Cajon and national city.

You do not want to become the laughing stock of the real estate professional community.The 350k property for 150k would be like a buyer coming to me and saying they want to find a brand new retail strip center at 4 to 5 million with national tenants for an 8.5 to 9 cap rate with brand new leases when the developer has a break even of a 10 cap in the property.

Originally posted by @Michael Zar:Guaranty National Title Company.

With that being said, I'd like to see data trends (population changes, % of renters per area, business growth, etc.) for both the Kansas City area, then nationally in other markets as well if that's available.