You are not required by law to employ an architect in the United Kingdom. This implies you can design the structure independently and hire a contractor to execute the plan.
Most of the time, it costs less to start from scratch. Remember that if you want to tear down an existing building, you will also have to pay for the demolition, which can be very expensive. You'll also have to think about how this will affect your schedule and how it will affect your neighbours.
In the realm of home improvement, there are four primary categories: the essentials, the aesthetics, the value, and the personal.
The key difference between the two is that renovation often refers to returning anything to a decent condition or state of repair, that is, restoring a structure, window, or door to its previous condition. Cleaning, restocking, and sprucing up are all parts of the refurbishment process.