What is the law that governs the making of all cars?
Answers:
Department of Transport will give you all the answers you require.
to make a profit out of selling them?
You will find that there are 'Constructuin and use regulations' which every vehicle sold in the U.K. has to pass. The manufactorers submit each model to the Dept of Transport for inspection and only if it passes this inspection can it be sold or used on the road. If you were to build a car or significantly modify one the same would apply.
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