Gray Line from Sea-Tac to Ship?

[Lessa11]

I'm looking for the cheapest way to get from the airport to NCL at Pier 66. I found this company called Gray line that charges $18pp RT (kids $13) or $11 one way (kids $8.25) from the airport to various hotels downtown. For $3 more, it says they'll go to the Marriott Waterfront Hotel which is across the street from the terminal. Has anyone done this? Is it a good idea? So for my family it will cost us about $40 one way or $67 RT. Is a cab or town-car about the same price?

[n0w0rn3v3r]

A cab is more expensive from Sea-Tac. You can also try Shuttle Express.

[NWWanderer]

A taxi will be $40-45 plus tip.