is $1500-$2000 enough for a good gaming PC?

I have decided to buy a Gaming PC. I am unsure still whether i will put it together with help from a friend who has done it or whether i will buy a already built one online. I am just wandering if $1500-2000 (Australian) is enough for a solid gaming PC that can play games like Bf4, watchdogs, gta5(if released) on high settings. If i do get one for $1500 how long until i would need an upgrade. This $1500 does not include desktop, mouse, keyboard. I have other money for that. :) It's also worth noting that i dont really know much about PC's... im happy to learn though so any useful links to sites with information would be good :) ps. what are all the parts that i will need? Any recommendations on good games is also appreciated. Thank you so much in advance :D