Not a bad shout Dom. How did you do it? They sent you money through paypal or...then you gave it back at the RR day?
It has been slightly different for the ones I have organised as The Doc has let us use his dyno foc & all the money was going to the forum charity, all I asked was people made a £5 donation to secure their place and paid the remainder a week before the day itself.
Your suggestion could work, it means a little bit of messing around on your part though.
Another alternative would be paypal a deposit to you & you then pay JKM the total of the deposits which will be deducted from each persons fee on the day?