Is it a really bad idea to project manage your own extension project or a brilliant route to cutting costs?

Exterior of a kitchen extension, with sliding doors to the garden, and a large picture window.

Is it a good idea to project manage your own extension? This is a question often asked by homeowners keen to add space to their houses without breaking the bank.

While it might sound simple to take control of your extension ideas, from the early planning stages up to completion, there is actually a lot more to it than it might at first appear.