Yeah.. I went a lil nuts.. and that doesnt include the 2 cats and dog.. which I still have vet bills to pay off from this month!
Well... if its pocket money I would approach your parents with pros and cons on different tanks and show them that even though this one might be a bit more than some other cheaper tanks in the long run it will work out cuz its a good size and will prob last longer..
If you earned the money i.e. job, house work.. it really is up to you what you do with that money..
also maybe try having them get you the tank for xmas.. or early bday present?? thats what I usually do when I want something but dont wanna pay.. lol down side is that if holiday or bday is far away you just wont get anything on the date.. but upside you still got something.