landlord refuse to refund part of montly rent, is it ok?

I live in Seattle, Washington state. In Nov 2009, after 18 months on a written lease, the landlord and I agreed on an oral basis the lease would be on a month to month basis. In early February I notified the landlord I would move out on March 13, together with the full amount of rent for March. Subsequently I moved out on March 13. Today I received a letter from the owner which states that since the lease had expired, she will not refund to me the rent for the 18 days I didn't live in the condo for March.
To me this is outrageous. We have always paid ahead of due date, never being late. It seems to me that the landlord is passing the burden of recent special assessment to us.
Also, she deducted from the security deposit the amount for cleaning window and baseboards. To me this is normal wear and tear and she has no right to deduct anything if we didn't damage anything, especially if we left the condo extremely clean before we moved, including have the carpet professionally cleaned (even though we kept good care of it).
I'm willing to legally challenge the landlord but want to hear your opinion first. Thanks in advance.

所有跟帖： 

• it will depend on the written lease agreement. -autumnmoon- ♀ (92 bytes) () 03/26/2010 postreply 06:43:19

• Thanks. The original lease for the first 18 months -DesertCamel- ♂ (497 bytes) () 03/26/2010 postreply 07:42:35

• Local law governs in this case. -CyberCat- ♂ (552 bytes) () 03/26/2010 postreply 10:50:36