Abstract: The present invention relates to a method for optimizing purchases of services related to construction sites, comprising: enabling constructors to provide requests that include items and quantities; enabling suppliers to provide offers to at least part of the items in each request; applying a cart comparison algorithm for ranging the cheapest available offers by said suppliers; applying a transportation comparison algorithm for finding the transport cost for each offer; generating range of packages corresponding to the request as provided by a specific constructor, wherein each package may include items from more than one supplier; and upon selecting a package by the constructor, executing an order to each supplier and transportation service that appears in the selected package.