Oregon State tax

Both me and my wife live in WA state. I physically go to work in OR every day. There are some days when I do work remotely from my home in WA. I was told by some friends that for the days I work remotely from my home in WA state I don't pay OR tax specifically for those days. I have two questions:

1. How can I claim a refund in my OR taxes for the days that I worked remotely from my home in WA state?

2. What proof would I need to have to get a reduction in taxes for OR for days that I worked remotely?

3. I get paid vacation days from my employer. Can I claim a deduction for the days that I was on vacation?