4P's of Marketing,Value Based Price ?

What is the most important among 4 p's of marketing ? Price? and which is the best strategy cost based or value based?

All P’s are integral part of marketing activities. They have their own importance.

Value based pricing is a business strategy. It sets selling prices on the perceived value to the customer, rather than on the actual cost of the product, the market price, competitor’s prices, or the historical price.

A cost is the value of money that has been used up to produce something, and hence is not available for use anymore. So cost based pricing means to set price on the basis of cost incurred on the product.