Apple won't repair my faulty iPhone?

I got my white iPhone 4s for my 16th birthday in December. I was on a school trip at ye end of march making my phone just 3 months old, I dropped it and a tiny crack appeared in the top right hand corner of the phone, the crack is so tiny it's barely viable and it doesn't go anywhere near the actual screen. Then a month later, my phones 4 months old now, the Wi-Fi button is greyed out and I can't turn it on or off or connect to any Wi-Fi. I rang apple and spent hours on the phone they said they'd fix it so I sent it away, they sent my phone away and I got it back 3 weeks later. I opened the box and to my horror they hadn't fixed and said I'd have to pay €120 for the Wi-Fi to get fixed. I brought it into an iPhone repair shop in town and the man did everything he could to fix it and nothing worked he explained that there was an actual fault with the phone and that me dropping it had nothing to do with it. A few weeks later I decided I would start using my iPhone again as I thought it might work again after being switched off for so long. I turn it on and my silent button and volume buttons weren't working. I returned it to the man in town and asked if he had done something he showed me how everything is connected to one cable and that by the end of summer I'd be lucky to turn the phone on because the phone was never tested and everything would slowly break. My iPhone is still in warranty until December but apple say that the warranty is gone off it because I dropped it but the phone itself is actually faulty. Please help I really need some advice on what to do!

Sell it for parts and buy a new one.