I promise you I'll earn it all back.

My mom and I went to look for a piano today, again, because now my mother thinks it's smart to rent a piano before actually buying it. Well I think so too. But now my dad totally disagrees with me, buying a piano. He thinks that I won't even touch it after having one for 2 months. I don't think it'd be that way, but I understand why he thinks like that. It happened a few times before that I got something new, loved it for 2 months and then I didn't do a thing with it anymore. Now if we'd rent a piano, then we could rent it for max. 1 year, then he could see if I'd actually keep playing it. And if I would, then my dad could see me many more times; I'm usually upstairs, but hey, I'm not stupid, I wouldn't put a piano in my own room, I'd put it downstairs. If I'd keep playing the piano all along, I'd be more downstairs and that is what my family wants, too, they want me to use the things I get and they want me to be downstairs most of the time. Now if we'd rent a piano, even if it was just for 2 months, then my vacation would be less bored. I'd do anything just to keep the piano, like, when school starts again I'll be busy again, but I'd just come home and don't allow myself to go upstairs until like, 5 PM or something so I could make my homework downstairs and then play the piano. Really, anything for a piano. Just anything.
But of course my dad won't believe me, now how could I convince him? I don't think I can. Plus we saw a good piano that we could rent, but that's 39 euros per month and the first month it costs about 500 euros. And we're not very rich, my mom still has 3 jobs and I have zero, and I can't get any jobs either. It's so annoying, I'd really work for it, but I don't know how. I somehow want to convince them I really want a piano and that I'd work for it, BUT HOW?
And if I'd get a piano, I'd somehow want to earn it all back, just for them, to show that I really love them for letting me buy a piano, with a part of their money of course.
And today, "The Piano Style of Amy Lee with piano and vocal music sheets" arrived. :D FINALLY. :)