During designing stage with architect, we call other consultant/contractor like Building Contractor, Water & drainage consultant/contractor, Electrical Consultant, IT consultant, HVAC Consultant, Gas pipeline contactor etc. We will take quotations from them. We make comparative statement according to technical things and price. We select two to three persons with suitable price and technical requirements. The promoter will negotiate the price and give appointment to the consultant/contractor. It is very much necessary for appointment of the contractor/consultant at the time of architect start work. So during design of the building only necessary precaution will be taken care of. We keep watch on all the process and if we found anything out of order immediately we take action on that.