Selling a rental with a long-term tenant. What about the deposit?

[Matt Gilroy]

I have had the same tenant in my rental for approximately 5 1/2 years.  I'm considering selling it and getting something else.  I'm confident that the deposit that was given to me before he moved in won't cover the years of wear and tear on the flooring, paint, overall upkeep, etc.  

If I sell the rental property with him in it, do I need to refund the deposit or ??

This is in Washington State.  Thanks!