Once you have found the contractor you want to work with, and if you decided to supply the material for the project yourself, your next step will be to negotiate with material suppliers.
Firstly, you need to understand that the price you pay as a consumer is about 25 to 50 percent more than the price a contractor who regularly buys a particular product will pay.
Most manufacturers, distributors and suppliers of building-related products will have two very different price lists or pricing structures - one for members of the public and one for the trade clients.
The main difference is that trade clients tend to buy in large volumes. They usually have accounts with the relevant manufacturers or suppliers and they probably buy from them regularly. Loyalty counts for a great deal, and suppliers often renew the bigger clients with favourable pricing.