Yeah - this is a decal...but I can only guess at the cost as it's not WHAT you know....Seriously though, I own a graphics business but I can't quite make printed graphics as large as this one is going to be. Fortunately for me my sailing compadre is also in the graphics business and works at a place with considerably larger equipment!
It's a solvent ink that is printed by a large format printer (48" wide so these will be printed side by side) to a vinyl substrate. The graphic is removed from the machine, manually laminated, fed back into the machine, re-aligned, and contour cut. It's not easy or inexpensive. The printer/cutter alone is over $18k!
Full color print substantially adds to the cost of the graphic. If you can use solid contour cut vinyl (no printing - as in the above examples) the price becomes a good bit more reasonable.