Site analysis and feasibility is the step that can be critical for a project. It basically requires researching a site to see if it is profitable. Property developing can hold hidden costs.
To find out what cost are required it pays to call professionals to find out costs.
Call your local council for all required costs required to have all utilities connected / upgraded for your project.
Architects are excellent source for determining costs like council approval costs including drawing required.
Construction cost can be very important as many projects where new buildings will be built the construction costs are a large part of a project. The last important piece of information is sale price because if you can not sell your product for enough (or it sits on the market for a long time) the project will not be feasible.
Feasibility Study Decision
And do not forget to have an exit strategy at all phases!