Storing a car over winter

For best results:

Use a fuel stabiliser.

Disconnect or trickle charge battery.

Put extra air in tyres, or raise the car on blocks to prevent flat spots.

Make sure it’s squeaky clean and waxed.

Put a cover over the car to prevent dust and moisture.

I would be inclined to sell a car if going away long-term, presumably you had your reason for keeping it.

PS, One 0ther point I vaguely remember. They also advised to squirt a few drops of oil into each cylinder. However as not too sure I just did a "Google" to check and :-

Yes, squirting a lubricant into each cylinder is a recommended practice for long-term car storage (generally more than a few months) to prevent rust and corrosion on the cylinder walls and piston rings

. However, it is generally better to use a dedicated 

engine fogging oil

 than regular motor oil. 

"

Why use fogging oil?Regular motor oil can drain quickly and may not provide a lasting protective barrier against moisture. Dedicated fogging oils are designed specifically to coat internal metal parts with a waxy, protective layer that resists corrosion and stays in place for extended periods. The Procedure for Cylinder ProtectionFollow these steps to properly lubricate the cylinders for storage: 

• Change the engine oil. Always store the engine with fresh, clean oil, as used oil contains contaminants and acids that can cause internal corrosion over time.
• Remove the spark plugs. Access each cylinder by taking out its corresponding spark plug.
• Apply the lubricant. Spray the fogging oil (following the product's instructions) into each spark plug hole for a few seconds. As an alternative, a small amount of low-viscosity penetrating oil or Marvel Mystery Oil can be used, limiting the quantity to about half an ounce (15cc) per cylinder.
• Rotate the engine manually. To distribute the oil evenly across the cylinder walls, use a socket wrench on the crankshaft pulley bolt to manually turn the engine over a few revolutions. This ensures the entire surface is coated.
• Reinstall spark plugs. Put the spark plugs back in and tighten them appropriately. 

Other Essential Long-Term Storage TipsLubricating the cylinders is only one part of preparing a car for lengthy storage. Other critical steps include: 

• Fuel system: Fill the gas tank completely and add a quality fuel stabilizer to prevent condensation and fuel degradation. Run the engine for 5–10 minutes afterward to circulate the stabilized fuel.
• Battery: Disconnect the negative terminal or, ideally, remove the battery and connect it to a smart battery maintainer (trickle charger) in a cool, dry place.
• Tires: Inflate the tires to the maximum recommended PSI or place the car on jack stands to prevent flat spots.
• Pest prevention: Block the tailpipe and other openings with steel wool or rags to deter rodents and pests.
• Environment: Store the vehicle in a dry, well-ventilated area, and use a breathable car cover.