Sub-letting a rented parking space - what do I need to know?

[fluffyanimal]

I've just taken up a year-long contract for a rented parking space near where I work, however I won't be needing it for the first 3 months. It's still cheaper than paying to park in the public car-park nearby, but ideally I'd like to recoup some money for those months I won't be needing it. The owners are happy for me to sub-let it so long as whoever I find is happy to abide by the same T&C as I signed up to.

I've had no joy finding anyone at work who might take it, so I'm considering searching wider by using internet forums etc. But I'm worried about finding a sub-lettee who might not give the space back after the 3 months. How do I protect myself and the parking space owners?

How will you deal with it if they park a wrecked car on it and then vanish? You are going to have to pay for the removal.

Similarly if somebody wrecks it you will be liable. And that will include oil leaking, which is common.

Are you really going to make alot of money over three months to make it worth while?

Urg. Stuff I hadn't considered. Thanks.