What is the best way to deal with tolls?

I paid cash for tolls

They have a transponder you can get with the vehicle. Best and easiest way to do it, they just add it to your bill at end of rental.

Depends how many times to intend to drive on the toll. If many or for just convenience, there's a website you can buy in advance a toll pass. Sorry, but don't recall the website. Look on Google and try typing in Sea-Tac toll pass.

They are just added to your bill, no big deal, easy.