its very similar to what it cost me and Thomas to come over to the UK everytime

Accomodation - Usually around £100
Fuel - At least 3 tanks @£70 each so £210
Ferry/Chunnel - about £100 (Ferry is usually cheaper than the tunnel)
Food/eating out
Show tickets

I never bothered with breakdown recovery, didnt even have that in NL and of course the cost of the laps is not there but it was easily £500 minimum each time