Readers' forum : Pirate radio

I have two clients who host websites and receive a payment from service providers but I am confused about the VAT treatment of the fees they earn.

In the first situation the site brings together owners of luxury cars with those who want to rent them. The renters make full payment to my client for the hire before my client deducts 20% of the income and pays it to the car business.

A similar situation exists for the second business but this involves the services of disc jockeys usually in relation to private functions at which the party host needs some music.

My question is simple: as far as the VAT registration threshold is concerned is the relevant turnover figure for the clients based on the full payment made by the punters? Alternatively is it just the net commission retained by my clients?

I...