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Up to three months
If storing a car for up to three months you should attend to the following in addition to the one month items
Hose under the wheel arches to remove accumulated mud. Wash the vehicle then polish, apply a chrome protective polish where appropriate. Let the car dry thoroughly before putting it away.
Remove the battery (Check the code of any coded radio before removing a battery lead, and you must find out if any on-board computer will be affected by having the battery disconnected for a long period of time. Refer to the vehicle owner's handbook.), clean the terminals, top up if required (if it's not a sealed for life battery) and arrange for it to be slow / trickle charged about every 4 to 6 weeks. Don't leave it where it may freeze. Some special chargers can be left on all the time.
Raise or remove the carpets if dampness is suspected and dry thoroughly.
Make sure the wiper blades are not in contact with the front or rear screens.
Empty the windscreen washer bottle.
If the vehicle is not to be parked on the public highway you should consider getting a refund on your road tax by declaring Statutory Off Road Notification (SORN) on the refund application form. You can read more details on the DVLA website.You may also be able to reduce your insurance cover to fire and theft only.
If the car is in a garage, make sure that there's plenty of ventilation - gaps under the doors and a high-level air vent to promote circulation.
An alternative is to use a dehumidifier, in which case the garage should be sealed as far as possible. Dehumidifying is cheaper and probably better than heating a garage, though a dehumidifier will need a low-temperature shut-off thermostat as they can't work below about 4C. Corrosion is in fact not a problem in very cold weather, provided the car is dry and free from road salt.
