The Price Of Passage is an unmarked secondary quest in The Witcher 3: Wild Hunt where Geralt can encounter some guards trying to extort some coin out of him.
When traveling in Oxenfurt, you will be approached by two Redanian soldiers asking for a "war tax." They can be found under the archway leading from the Oxenfurt Harbor signpost to the marketplace. You have two options:
Option 1: Pay Them Edit
This will cost you 50 . You can them find them a few days later, loitering at Oxenfurt’s south gate. They will again ask for more money, and you again can choose to pay them (again) or refuse. If you pay again, you'll never see them after this, but if you refuse, you may run into them on the outskirts of Oxenfurt a few days later. They will be angry at you for getting them in trouble. You can choose to fight them with your fists or kill them with your sword. The quest will then end.
Option 2: Refuse to Pay Edit
They will call their superior and accuse you of being a spy. The superior will not take the bait and will threaten to send them straight into battle for extorting money. The quest finishes and you can be on your way.