Please google PL 111-22 which will answer some of your questions. The reason the attorney may be threatening 21 days is because he may think you are not a bona fide tenant - in other words, that the previous owner was your sister-in-law, or something like that.
I have a legal guide on Tenant's Remedies Post-Foreclosure; if this property was not foreclosed they may not apply to you. In the worst case, if you do not have a lease, then the new owner *could* give you a 20day notice of termination of tenancy and if you did not leave, then they could commence an eviction.
But (and this is a BIg but) - a 20 day notice has to be served on you , the tenants, allowing at least 20 days until the end of the rental period before they have standing to evict you. If you would normally pay rent on the first, the notice *has* to arrive on or before the 10th to be effective on the 31st. Lawyers who do not regularly practice landlord tenant law in WA miss this requirement. If you were to receive a 20-day notice today, for example, the only thing you'd be responsible for would be to be on your way on or before August 31. It is too late in the month to ask you to leave pursuant to a 20-day in July.
So I doubt they are fishing for reasons, they don't need a reason if you don't have a lease.
Don't hesitate to contact me if you need more assistance. Elizabeth Powell
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