1. Hacking is hard, don't hack, there aren't many hacks public anyways.
2. FR-F2 is one of the best Snipers in the game also it's perfect for Quick Switch. if you don't like it, go for TPG.
3. Yes, in order to get G Coin weapons you will have to buy G Coins with money, I suggest you find a good starters account here and buy it.