For the average rollercoaster, $15 million (US) and they are becoming more expensive.
I believe it was 30 million.
The tallest coaster in the world is kingda ka, and the price is mind-boggling: $25,000,000
$12,000,000 USD .coaster-net.com/ridegallery.php?action=display&id=78
Expedition Everest
$23.58
5 cents and a bj
$ 10
Your whole life savings... im sorry):
It may cost $ 5000 . 100000 , because they sometimes cost $ 700 . 1000 .
14,000,000 dollars
Maybe between 2 and 3 million dollars!!
The challenge being the cost, and efficiency of wooden materials, along with having to hire professionals to develop rides, and to provide extra material to prevent destruction of the wood.