Cost Analysis for a project located in North West London

We have been appointed to carry out a Cost Analysis for a project located in North West London.
The project consists of a demolition and site clearance of existing dwelling and erection of new 3 storey detached dwelling comprising ground, first and second floors, erection of single storey pool building in rear garden and implementation of both hard and soft landscaping works, including driveways, patios, paths, boundary treatments and any necessary regrading.
GIA is circa 8,000 sqft