How to get a Marquee cheaply?

Its my 21st birthday at the start of April. I'm having it at home and keeping it simple. The house wouldn't have enough space for people and there needs to be an area where people can go to smoke and a lot of my friends smoke and on my 21st I don't want people going out in the dark and maybe the rain.

I don't have a lot of money to allocate to the party as I'm a student and I have a lot of other things to pay for and my parents wouldn't have much money either so I'm wondering does anyone know of a company in Ireland (Limerick) that does good rates on marquees or is there a way I could borrow one off an organization by making a donation?

Thanks any help appreciated!