S-B-D,
I'm under the impression with such arrangements any expensives you could prove were incurred due to that business would be claimable - items such as petrol, food at the airport, ID pass, parking, etc should all be tax deductable.
That's not tax advice incidentally - although i wonder why so many people keep silent about their own arrangements, i'd be very interested to hear what people have worked out.
Horgy