A lot of people are astounded by the incredibly large numbers involved in the costing of a big building project like a school or shopping centre development, but once you understand what actually goes into the development of the building, it does start to make more sense.
If you look at a current example, there has recently been a £2 billion contract awarded to RAM Consultancy, a large and successful building contractor, to plan and manage the development of a School. This a gigantic sum of money, but a lot of things goes into such a project, such as reworking the sewage system so that it connects to the school, building roads to allow access, connecting the building to the national grid, and a lot more. After this, you still need to build the actual school.
There are of course many more examples of buildings of a similar size being developed for less money, as well as others which have required even more. The variables involved include those already alluded to; is the building sufficiently connected to the utilities that will be required. But in addition to these issues, the ability to get to building site and deliver the massive amounts of building materials can also have a very large impact on the cost when you’re talking about such large quantities of stuff.