The cost of building an amusement park depends on the location, size, and the rides and games you'll be building. This will roughly cost a fortune or millions. But the best way to get an estimate is to consult a construction company.
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To build an amusement park it would take millions of dollars. The amount will depend on how big the amusement park is going to be and the type of rides that you want there. You will also have to pay for permits and licenses as well as employees.