VAT and locum GPs

I have inherited two locum medical general practitioners who trade through personal limited companies. Doctor A sources most of his work through various agencies although his company invoices one NHS hospital directly albeit fairly infrequently. His business turnover is more than the VAT threshold but he is not VAT registered.

Doctor B sources all his work through an agency. His business turnover is around the VAT threshold and he is VAT registered. He charges VAT to the agency and makes a flat rate VAT profit. There does not seem to be a problem with this arrangement.

Doctor A would also like to benefit from the flat rate scheme and has asked for advice. My questions are as follows.

• Does the personal service company supply services or staff?
• Would the NHS hospital take a dim view of being charged VAT by...