The place where you live/location: Insurance in California, especially los angeles is far more expensive than say Kansas.
The price and cost of reconstruction: The selling price and the assessed asset value play a huge factor in how much you pay because that's how much your "insured" for.
The amount of the coverage: Say you want part A, Part B, and Part C and you want to maximize the coverage then your cost skyrockets up because the dwelling coverage could go up to 500,000 but then you would have to pay an extra 100 bucks a month.