WHAT ARE GROWING FACTORS OF SALE,WHILE CONSIDERING THE COST OF PRODUCT AND COMPETITOR ANALYSIS REGARDING TO SALE PERSPECTIVE?

I agree with Mr.Nasir.

to have a full coverage you have to start with research to know the Market demand and evaluate which segment would be profitable according to your cost , then you should target them, based on your value proposition , after that design you marketing mix to satisfy your audience needs, and of course you should put in your consideration Economics trends and the competition 

According to me coast of product doesnt matter, we shuld have gud compiteter in field so that we can grow up soon by comparing the product with each other but not by the coast of product

Difficult to understand the true essence of your question........ what i believe is to have a keen eye on the following factors for the smooth & desired growth of your product:

1 - Study of the market (4P's)

2 - Study of the competition

3 - Economic trend

4 - Market demand

5 - Class of targeted customers