Where can I rent a guitar?

Hi everybody, does anybody of you know if there's a shop that rent guitars? I have the final exam for my Masters Degree in September and I can't afford to spend three weeks without reharse the pieces I have to play for the exam. I've asked to a friend of mine, whom lives in Los Cristianos (I believe...) and couldn't help me in any way. She asked to a local store and they told her they don't rent musical instruments. I can't even take my own classical guitar with me, since I have to switch boarding companies in Spain plus I'm too afraid to put it in the hold: it costed me a whole lotta money and it would be a pity to pull it out of the case completely smashed. Anyone of you guys can help me with this? Even a cheap guitar will do the job, I just need something to keep both my hands in shape.
Cheers!
Orazio.