Find a part seller and go for an i5-6600 and RX580 or GTX 1060, 16gb of ram and a decent psu (at least 80plus certified). With that you'll be able to play most games at 1080/60+fps with ultra settings. Many part vendors offer themselves to build the pc for you so go for that if you don't want to build it yourself.
I guess it'll cost you about 750$ or so including the 50$ building price (if you look for good prices on places such as newegg). The Windows license you can borrow from our friend Jack Sparrow (unless you want to pay 80 bucks for a legit copy), you could also use grey market and buy a 10$ license from G2A or the likes.
Add 150$ on top of that for a monitor + kb+m. So yeah for 900$ you could get a PC that destroys the PS4, PS4 Pro and XB1. A bit expensive on the short run but with free multiplayer and cheap games much cheaper than consoles on the long run.
