Tenants come and go as do neighbors but you don't want to run the risk of making them not like you for bringing in people they may feel are undesirable. 

For the last three years I've owned multiple rental properties in an undesirable area in California with good cash flow.

I believe that a property doesn't rent, in most cases, for one of two reasons:1) The property itself (i.e. condition, location, other undesirable factors, etc)Or 2) It's priced too high.

A Group Home may be seen as an undesirable business/addition to the neighborhood to some of the local residents...

Regarding Dr Philips, are there undesirable areas?

Basically want to know the areas to absolutely avoid that are high crime and known for undesirable tenants.

Is it just as easy to terminate a MTM lease with an undesirable tenant as it is with a 1yr lease? 

(It sounds like the rest of the items, while undesirable, are not sue-worthy, so to speak).So ask yourself this -- you have a landlord who is basically not doing what he's supposed to from your vantage point, and you want to sue.

My only advice to tag onto that is find properties in peripheral neighborhoods and buy at least 4 homes on the street.

Something like: "We do not rent to lawyers, law students, drug dealers, <other undesirable but unprotected groups>" How do you phrase your rejection letter to a lawyer and what if that lawyer is also a member of a protected class?