trespass or not

Check your purchase contract, I suspect you do not own your parking space, it is usually owned by the OMC and you lease it or use it under license for the duration of your ownership.

1) You don't own the space, it's allocated to the property, but you don't even own the property. The OMC owns the apartment (and the space) and you have a long-term lease on it.

2) You cannot charge someone with trespassing on property which you do not own. In practice, you'd never get away with it even if you DID own it. There are plenty of car parks where it's impossible to get in/out without walking across multiple spaces associated with other properties.

3) Most of these leases will specify what you can/cannot leave in the space and I have NEVER seen one that allows for anything other then vehicles (cars, motorbikes, push-bikes). I've seen developments where there was trouble when someone installed an anti-theft pole that cages your car in because, technically, they weren't allowed for in the OMC documents.

4) Anyone who thinks all this is overkill should take a step back and think. These rules and regulations don't just appear out of the blue. People aren't just sticking them in for the hell of it, it's to reduce the impact on your neighbours of anything which could be deemed unacceptable. The reason for the rules I'm talking about in point 3 is because of people like the OP. I've seen skips, BBQs, ice-cream trucks, coffee-stalls, pigeon-lofts, and a whole manner of innocuous stuff left in spaces over the years. You have to nip the innocuous stuff in the bud or it leads to the other stuff.

Irish people are cnuts. Our post-colonial hangover ensures that property/land is a real sticking point for loads of people. We don't know how to live together, and cramming hundreds of people into smallish developments is just asking for trouble. You need the patience of a saint to live around loads of Irish apartments because they just don't give a bollocks, most of them. Rules prevent the worst of this happening. If you don't like it, sell the flat and get a detached house in the middle of Connacht so you can blare Daniel O'Donnell at full volume and leave your birdcages wherever you want.