What do I have to pay when getting a new Iphone?

I'm not really good at understanding phone contract plans. So I have an Iphone 4S, and my 2 year contract with O2 is ending now. I want to have the Iphone 6 16GB now as my new phone. The plan that I saw on O2 says that I have to pay 29.99£ up front, and then 43£ per month for the next 24 months. So, what I don't get is, is this EVERYTHING that I will have to pay, or will I also have to actually buy the Iphone first, for whatevre price it is, let's say 200£. Is the price of the Iphone itself already included in those 43£ I will pay monthly, or not? Am I gonna be paying the cost of the Iphone in 24 separate instalments or do I have to pay a price when I go into the store? Because I don't see anything saying about the price of the phone itself. Please help me I'm really dumb.

Added (1). I don't really remember the process I went through when buying my Iphone 4S, that's why I'm kind of lost. I know I pay 41 pounds each month for O2. I don't remember what I paid when I got the Iphone 4S 2 years ago.

Does she like me because of money?

I just met this girl 3 days ago, she's 18 years old, she clearly shows signs that she likes me, she already introduced me to a lot of her friends but she seems much interested in my toys so much, she talks about my headphones, my iphone and stuff like that, and today she was already asking me what i intend to present her friend as a birthday gift which will be tomorrow. She is suggesting that i give her friend money to buy her own gift. I really like this girl but i'm begging to think she likes me because of money or something… Please help me understand something… All suggestions are welcome… Thank you

My iPhone 4 is not turning on

I bought a iPhone 4 off ebay, when it came it had all the old users photos and music on so I decided to erase all content and settings, after id did that it turned off then asked me to put my sim in, witch I did, then it still wouldn't turn on, everytime I slide across it sends me to emergency call, the phone is not stolen or blocked as it was bought off a lady.