I leave my car in a similar storage facility near me when I'm out of the country. When I bought my previous CLS the insurance company said I couldn't leave it on the drive if I was going to be out of the country for more than 14 days, otherwise my insurance would be heavily loaded, and this was before key less theft and the like came to prominence.
The place I keep my cars is practically impossible to find, a completely innocuous and unassuming building hiding treasure trove of cars! (alas, no pictures). Obviously, being in the Midlands its a little cheaper, I pay £2.60 per day plus vat. That's the 'deep storage' price, as in buried behind a number of cars and more than a few days notice is required. You can pay I think £3.10 per day plus VAT for short notice access, typically the night before, but not Sundays.
People say the car owes you a lot if you start to store it, but I have looked at renting garages near by and this starts to get real expensive especially if you want power. I don't really want to move, but I do keep looking and the cost of a house with adequate storeage adds considerably more than £100 per month, per car to my current mortgage...