Property Manager responsibilities collecting on previous tenant

[Jacob Lewis]

Hi!  I haven't managed to find anything on this so maybe it's not so cut and dry.  I've had a rental in California for about 10 years, managed by the same property manager, and now I'm ready to sell.  The tenant moved out leaving a big mess and about $1500 in unpaid rent.  

I'm expecting the property manager to follow through on collecting repair costs and unpaid rent, going to collections or representing us in court if necessary.  But they insist that since I'm selling the property and they're not managing it anymore they will kindly pass along our bill to the tenant but not go to collections for us.

Does that seem right, given that the tenants fell behind in rent on this manager's watch?  As well as kept dogs which violated the lease and incurred extra repair costs, on this manager's watch?  Is there any law about what a manager is responsible for, or any recourse I can take?

Thanks!