Your parents have probably planned based on the fact that you can get in-state tuition for free. They probably have not saved additional $ for your college because of this.
You say you have free tuition…but do you have meals/housing covered too?
So if you want to apply OOS, make sure you find a place where you can get tuition covered through scholarships.
This can be need based or merit based.
Ask your parents to fill out the Net Price Calculator for a college of choice. See if you would get need based aid. if not, you need to find merit based aid. Look here for ideas: http://automaticfulltuition.yolasite.com/
if neither of that would work, then the other option is to have you take out loans. But why on earth do you want that (if your parents would even co-sign?) Going out of state seems cool and glamorous, but I assure you that later on you will be kicking yourself that you have to pay $1000/month in loans. You are only 17, but you have the rest of your life to go live somewhere else. Right now it seems like you have to go to college elsewhere…but you don’t. You can get a job in another state after you graduate.
So go somewhere that doesn’t cost more than WA if you don’t want WA. But do it without taking loans/making your parents pay.