Know-How Exchange : Student Questions

dear all, my question is how to find out projections and prizing for the project? i have seen many a times that the marketing people find out projections on the marketing plan. basically what points should be considered for it? how to show, the revenue will increase of what percentage? how much of benefit the organisation will get on current plan etc. and second question is how to estimate total cost of project. how to find out, how much of money will require for the project? which the points should be considered for the prizing and how to categorize them etc...