How much would an iPhone cost per month? - 2

I'm fifteen, and for the longest time I have been contemplating asking my mom an iPhone, but I always end up not asking her because it's so expensive! I wanted to get an idea of how much the iPhone would cost per month for AT&T. Right now I have an LG Xenon that has been available for upgrade for a while now. We currently have an unlimited family texting plan, 700 talking minutes, and my brother has a 3 GB data plan for his phone. About how much would it cost per month if I were to upgrade to an iPhone 4 or 4s with perhaps the second lowest data plan?

Here's the AT&T website.http://www.att.com/shop/wireless/plans/individualplans.html It tells you all the types of plans they have and how much. Well, for the data plan (which is required to get) you can get 200mb which is $15.00 per month, or the 2gb plan which is $25.00-$30.00 per month. Then, text messaging is about $20.00 if you want unlimited. In my opinion I think the minutes for calling is the most expensive. 450 minutes for $40.00! Like, really! It all really depends on how much data you think you'll be using with the iPhone. I think it's definitely worth it. So it'd cost around $50-$90 dollars at least. Try going to the AT&T store and asking them about it. They have a packet that assorts everything out much easier than looking online.