MIL Got her Power shut off, need advice about the landlord.

Hi all,

To start, I'm not intensely familiar with the situation, so this is all how it was perceived to me.
She has had problems with this landlord before, and so this is not the first time.

She recently got her power shut off, and supposedly, the owner had set up an account for the local energy company to pay it on her behalf, having her pay him every 6 months (weird?)

Now, the power company is saying tough shenanigans and pay us $1200 to get it back.
She asked why she didn't get a notice at her door, and they said they mailed one to her, but here's where another problem lays... the landlord has not given her the key to her mailbox in the 6 months she has lived there. It is a community cluster box, which USPS wants $85 to re-key (I'm about to just pay it myself holy shit), but the landlord never provided a key for her mailbox unit. To my understanding, aren't tenants supposed to have the right to receive mail, unless otherwise specified in the lease? (this had nothing about mail, just a super generic one).

Previously, her water had been shut off soon after she moved in, then realized the landlord also wasn't paying the water, she paid it up and got it turned back on, then it was moved into her name, but also realized she thinks the landlord was upcharging on the water, as he was charging in the low to mid $200's, and on average, it is now $120ish directly.

There was also a time where in her third month, she had discussed prior asking if it would be okay to have rent a day after it was due, because of how her paychecks lined up, to of which they said yeah no sweat, but then the first came around and he started banging on her door saying he was going to evict her for late rent.

Snohomish County, Washington State.