First, read the Self Build FAQ on this forum. Read the other relevant posts on this forum. There are many, some only recently answered on this subject.
There are also several showing you the pitfalls of the direct labour route, insurance, certification, H&S, etc.
If people are working directly for you on site you have the responsibilities of a Contractor under the Health and Safety legislation and you will need full Contractor's insurance.
Unless you are competent to discharge the duties and take on the role of a contractor you should think twice about this approach.
Appointing a main contractor absolves you from this and from a vertical learning curve, as well as this project taking over your life for the duration.
Then the choice is yours.
ONQ
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