In my ad for the rental, I set some guidelines that should help weed out some undesirable tenants.  

Rohit, I'd say generally to focus on the peripheral sides of Austin - East or South.

Prices in Fresno for all but the most undesirable neighborhoods are getting too high to cash flow for sfr's but there are still  smaller apartment complexes in B and C neighborhoods  that may work for you. 

However, there are a lot of undesirable areas here.

@Ying Ding, I'd say generally to focus on the peripheral sides of Austin - East or South.

I am now a grumpy old landlady who can't seem to keep up with this ever growing pool of undesirable tenants who know too much!

The wholesale properties have either been too expensive, or in an undesirable area (I don't want to be a slum lord), or in a location too far away. 

Immovable undesirables (landfills, sewage plants).

In undesirable area's it is easier for you as a landlord to find section 8 tenants because you will be paid the rent on time by their voucher provider.

I have bought a few what i call Tweaker parks.. you know full of drug addicts ,, convicts and other undesirables..