The only problem we've had is a dog that escapes and harasses the animal control officer.

You can ask why you are being harassed while everyone else is not. 

Ended up taking 12 eviction hearings, nearly three years and two orders of rent rebates (harassing her) before I made her life difficult enough for her to decide to leave. 

If his behavior is harassing, call the police and they can issue a "do not contact" order (PA term). 

You need to confirm that this is the code of law that your tenant quoted in the notice.Unless there is a very recent change in the Washington Landlord/Tenant laws, your tenant is bound by the terms of your lease and is liable for rent until end of the lease, except if the tenant is called to active military duty, victim of domestic violence/ stalking, victim of landlord's harassment or if the dwelling is unsafe to live in.Even though the tenant may still be liable for rent, since he has given notice of early termination, you must mitigate lost rent by putting in good faith effort to re-rent the property at fair market value.

(B) If the landlord makes an entry in violation of division (A)(8) of this section, makes a lawful entry in an unreasonable manner, or makes repeated demands for entry otherwise lawful that have the effect of harassing the tenant, the tenant may recover actual damages resulting from the entry or demands, obtain injunctive relief to prevent the recurrence of the conduct, and obtain a judgment for reasonable attorney's fees, or may terminate the rental agreement.

You gave some great advice on finding good contractors and not just looking for the lowest bid, so I'm not sure why you would feel that you need to harass @Kyle Waters about his hair.

Although I haven't seen the knob yet, tenants believe it was an attempted forced entry.This could be a case of a tenant being harassed by someone he/she knows and the solution could be to work with or remove tenant if viable data comes to light. 

Instruct the 'harassed' tenant to keep a contemporaneous and detailed list of perceived threats, harassing behaviors and obstruction of entry/exit. 

Simply approaching a tenant and offering them a $100k check to love out more than once is technically considered harassment and can land you in severe legal trouble.I would recommend Rosenberg & Estis LLP for L&T representation.