It will all depend on the storage, moisture, and preperation. In Carlsbad, California my 1969 Corvette sat in the previous owner's garage for 18 years. It had been driven in and put on blocks with no preperation. I had to replace the gas tank and brakes, tunup and fluid replacements and drove it home to South Dakota.
In a place like South Dakota where the weather changes every day, a unheated cement floor will be full of moisture. If the vehicle is not started every so often and driven, you are better off on leaving it in a dirt floor shed where moisture doesn't build up quite so much.
I like to go to a boat shop and get some marine engine fogging oil. The oil is sprayed into the carburetor when the engine is running and until the engine is smoking like crazy. Spray into the carb until the motor is shut off and stopps turning. We always ran Stabilizer in the gas and make sure it runs long enough to get into the carburetor. Grease the car and change the oils so they are fresh before you store it. This gets the impurities out of the engine, wwhich can be acidic to your engine.
