The Fixed Price Engagement Model fits the projects with well-defined requirements. This model can be applied where clients are able to specify sufficient details for the completion of their projects.
When the project has well-defined scope, specification and deployment plan, it can be executed in a fixed time at fixed price.
The price-agreement is decided in the beginning and is not subject to change in any condition. Hence it has a minimal administrative burden and associated risks.
The amount of payment is not dependent on the resources or time spent on the project.
This model works perfectly when all the details of software are well-defined and will be stable all through the process of the development.