Do not have iphone 5 password

Hi so a few days a guy sold me the iPhone 5 on the street and I know it's illegal and most likely stolen but I got a good price problem is the iPhone 5 is locked with the 4 digit password and I don't know what to do I want to connect it to iTunes on my computer and try to reset it but I don't really know what exactly to do and if the iPhone would even get unlocked because it was not synced into my computer originally. What should Ido? I tried going back and finding the guy but he wasn't there (no surprise) .Is there anything I can do?

If it a sim card password try 0000 or 1234 or 1111
Or you can just take out the sim

If its a iphone password you will have to reset it
By reset I mean restore it to factory defaults

http://osxdaily.com/2010/06/24/iphone-dfu-mode-explained-and-how-to-enter-dfu-mode-on-your-iphone/

Then just plug in the iphone to your pc and reninstall the ios

Search how to put it into dfu mode. I'm pretty sure you hold the home and power button for ten seconds (while its off), let go of the power button and hold it for 10 more seconds. Then connect to itunes