The car question was to be able to determine travel arrangements in Gatwick. I'd rather have a guest house 4 miles away on a bus route than 1 mile away on foot if I had those exams to do.
There is a (freebie?) bus from Horley to Battleship House, so may have been worth looking into.
There's some comfy airport hotels with a shuttle bus, too.
My last three questions are still valid. You've answered the first one.