Looking for a garage or car storage M25 J13 Staines/Windsor

[LunarOne]

I currently have three cars on my driveway, and the garage is also occupied with stuff including a motorcycle. I'm looking to buy another car, perhaps two. To that end I'm looking for garaging with power (for a trickle charger) or some good value accessible car storage. Is anyone aware of anything in the Staines/Egham/Virginia Water/Sunningdale/Windsor sort of area? Nothing very high value, but I have my eye on a couple of modern classics around 25-30 years old.

Thanks!