It's something that you can do by yourself, but I'd be potentially concerned about the implications of that, as if you mess up even the slightest technicality, you could be hit with having to pay the tenants' attorney fees.
Some areas to be particularly concerned about are the adequacy of your notice. While a 30 day notice for nonpayment of rent can technically be accomplished (i.e., as a 30 day for cause notice), a 30 day no cause notice is almost always a better, safer option, and it can be pursued in tandem with a 72 hour notice for nonpayment of rent.
To limit your own liabilities and to ensure that the process is expedited as much as possible, you should consult with a landlord/tenant attorney in your area.
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I agree with Mr. Parks. Oregon's Landlord-Tenant Act is weighted in tenants' favor and there are many technical rules a landlord must follow. Even innocent mistakes in when notice is given, how it is served, and what the notice says can easily cost a landlord additional time and money and sometimes they are even ordered to pay a tenant's attorney's fees. If you aren't experienced in serving tenants notices and going to court to evict them, you need to consult with a landlord-tenant attorney in your county to make sure your notice isn't defective BEFORE you file an eviction.
Even if your notice turns out to have been defective, you may not have lost that much time (or any depending on how much time they have left). The reason is that you can also serve a 72-hour notice for non-payment of rent (again, have a landlord-tenant attorney draft this for you or at least review yours). If it's the first 72-hour notice you've given these tenants, they'll have the opportunity to "cure" it by paying rent within the time specified, but you can always serve them a non-defective 30 day notice WITHOUT cause at the same time so that no matter what, you can file an eviction complaint at the end of the 30-day period.
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