Quickfile. Is it suitable for contractors?

Hi All, 08/08/19

My son has recently registered a limited company to become a contractor for an agency. He is going to be a consultant to the agency’s client companies and will bill the agency for the research he will be doing for those companies. Is Quickfile suitable for him considering that the agency is based in the USA but he will be paid in pounds sterling? Also, does anyone know whether he can be exempted from the IR35 taxation? He has previously worked as a contractor some years back but did not have to pay the ir35 tax at the time.

I would be extremely grateful if someone could guide me as to whether Quickfile would be suitable for his circumstances.

Thanks and regards