Costs of viking ship

As seen in YouTube at @simcityvn the cost of level 4 to maximum level 15 of viking ship is 227500  coins. From 9 to 10 is 38500 coins. From 14 to 15 is 85500 coins. At 15 we will get the 4th visual with 2 sails. So there are 4 visuals and not 3 as Lana stated