I've made the trip up the alcan one time and probably will one more time. After that I won't be back again. I do like it there but the haul through canada is a bear. Took me almost a week to get there in my van and did $2k in damages when I hit an unmarked frost heave right at the top of a rise. It was like jumping a curb straight on at about 45 MPH. That is how high the heave was and I wasn't on the ramp side of it, I got the abrupt edge. Gas averaged around $2.20 a liter but could have been higher. The further north you go, the more expensive the gas is and don't pass up a chance to get gas. What is that, like about $8 a gallon US? I think the ferry would cost more than the gas but wear and tear?
Everything is much more expensive in alaska. Goods get there by barge or plane. A lot of sites won't ship to alaska either.
SD lets you mail in for renewal or new plates, no vehicle inspection. I wonder how much that lifetime registration costs?