It turns on the terms in the lease and it is an eviction governed by the rules in RCW 59.12. et seq. The contract may contain terms regarding notice and if you do not follow those terms to the letter, your case can be dismissed and you could wind up owing your tenant's attorney fees.
If the landlord is a corporation of some kind, a layperson cannot represent that corporation in court, it needs an attorney.
The best advice I can offer is to find and hire a local attorney who specializes in evictions and who can handle the commercial element, because it is different from a residential eviction. Don Allen, Evan Loeffler, Randy Redford, Michael Walsh - in no particular order, each is very good and can help you.
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The first step is to serve a notice to comply or vacate for whatever violation the tenant is committing. If the tenant does not comply, you can start an eviction action. The typical commercial case takes between three and six weeks from the time you serve the complaint until the sheriff comes out to remove the tenant.
Commercial tenancies are largely governed by the rights in the lease agreement. You should read the lease carefully before giving a notice or starting a suit. If you do not have experience handling this type of matter, I recommend contacting an attorney who does commercial evictions either to handle the case for you or to give you guidance.