In FFXIV, everyone want to beat bosses because they will drop rare equips. But it's too hard to beat them. Rare weapons are rare and expensive in auction house.
If you have enough FFXIV Gil, there is no problem. To gain such big amount of Gil in short time, the only way is to buy it from FFXIV Gil selling sites.
Your best choice is MMOAH which is the NO.1 game currency store which provide the cheapest Final Fantasy XIV Gil. A variety of discounts are held whenever the festival arrives. You can get the cheapest Gil with the least amount of money from MMOAH.