I have the rare luxury of 60 days notice on a unit, and was wondering if renters think an ad up for a while is stale and undesirable?

Quit investing in undesirable areas.

Seeing we are trying to encourage long term rental this would be undesired.  

The seller knows it is undesirable to hold through the Winter, but sometimes doesn't know the real cost in terms of actual dollars.Consider taxes, insurance, utilities, HOA if applicable, estimated upkeep, etc to come up with a specific monthly holding cost for the property. 

However, I'm concerned about students being hesitant to rent off-campus due to the undesirable surrounding area  and safety issues (Picture USC for instance.

Anyone has any insight whether it's a great or undesirable city for rental properties?

I think once you add those expenses your Cap rate will decrease to an undesirable level.

I recently got a call from an individual about a couple of condos he owns, but i looked them up on zillow & the estimation was 49k & they were also in a very undesirable area.

I assume she is either living with you now, or is paying rent somewhere else, or is in a home that is essentially undesirable for her to continue to live in.  

If they don't comply, which they likely won't, give them notice that their tenancy is not being renewed and they have 30 days to be out.We have gotten rid of multiple undesirable tenants by not renewing month to month tenancy.