Son starting out in IT contracting..advice required please.

[Bitzer]

As said, if contracting for less than 6 months, use an umbrella company. Anything more, then Ltd Co.

I use SJD Accountancy, and Cater Allen for banking. I've been contracting for 5+ years and wouldn't consider a permie job again....or indeed an umbrella company

[ringram]

With 20+ years experience in IT my 2p.

Qualifications and study are mandatory.
Not just product quals, but also look at Prince2, togaf, itil, iso etc as appropriate.
Mix that in with experience and he will be unbeatable.

Waiting for someone else to train you is the road to wreck, ruin and servitude.