[Usernames Suck]

The way I see it, you have a few options here. Let's start with the toughest ones which would happen if your parents absolutely said no.

As you're not of age yet, you could do what they say. Go to the university they want. When you're older they may be more inclined to allow you to make your own choices. If not, you can always try to get a job or apply for a scholarship when that happens and then go to the university you want for a second degree or to continue yours. Even though it sounds like you won't have a lot of spare time, your university may have a special regulation for students who are also working at the same time. As an alternative, you could just put off going to university until you're old enough to have more of a say on your own.

The option I would suggest most is to have yet another conversation with your parents.

Your point of view makes sense to me. You sound like you're being responsible by looking for a university that would allow you better options in the future and by wanting to manage your time carefully.

At the same time, I can understand why your parents would be concerned, especially if this didn't work out for your siblings. It also makes sense that they would be somewhat worried about burdening others.

The best you can do is perhaps make a list of the ways in which attending the universities you want would be better. If there are articles about them being good universities or about them offering opportunities you can't get elsewhere, print them out. One thing you should focus a lot on is academics. If your university of choice offers better classes in something you want to specialize in or if has your country's leading experts as professors then you should show your parents that. For example, if you're going to History and you'd like to specialize in 20th century History one day, of course that right now you'll be studying a little bit of all centuries but it makes more sense to choose the university that has better classes about 20th century History. If you're studying Medicine and the university you want has your country's most renowned surgeon as a professor that's important. If you're studying something that requires practical work in a laboratory or a studio and those facilities are better then show your parents that. Another thing you should focus on are additional services, like medical care, employment help offices, and other such things that are probably important to your parents as well. Basically, find everything that is better about the universities you want and show them that.

On your everyday life, do your best to show that you are responsible and mature. Do your chores, be polite, study hard, things like that that will show your parents they can trust you to live away from them. You could also point out that just because your siblings made mistakes or did things your parents don't approve of it doesn't mean that you're going to do the same thing and you should also be allowed the same good opportunities they had. Just because your siblings wasted those good opportunities it's not fair for you to get worse opportunities. Show your parents they've raised you well and that this is your chance to prove they've done a good job of that. If you're living with your aunt then I assume she'll be keeping an eye on you so you can point this out to your parents.

When it comes to your parents thinking you're going to be imposing on other people, there are some things you could do. If you would be sharing a house with other students, you would not be imposing on them: you would have as much right to be there as anyone else. If you were renting a room at a family's house then you were paying to use that room as long as you were respectful. Your aunt offered for you to stay there so you can try to talk to her, explain the situation, and ask her to help you convince your parents. Maybe your parents can feel better if they help pay for your living costs at her house, which wouldn't be so expensive as they wouldn't spending the money on the food, electricity and water you would be using in their home.