Those fluids? For oil, once a parts guy told me a website from an oil analysis organization, I remember they did an experiment, after two years sitting in a conainer, the oil content had no quantative difference except slight moisture in it. Once engine is hot, that will be vaporized. In practical level, it is a non-factor.
As for fuel, gasoline isn't like diesel fuel - over extended time it could grow algae, gasoline in half a year will not likely to change its characters causing fuel tank damage.
Other fluids will be near or just like that if you drive the car for the same period of time.
I might be wrong but if I were the poster, I'd only need to take care of battery, that is it.