I'm a fan of what Graham does at the recording revolution and this oe is a quick ad easy overview of his 300USD hoe studio, which is part one of a series.
http://therecordingrevolution.com/2015/03/26/the-complete-300-home-studio-and-my-new-challenge/
Out of curiosity, what have you got invested in your studio?
I've got about R4700 in my basic setup (before plugins & instruments & toys)
Interface : Roland Quad Capture (R1600 used)
Mic : Rode M3 (R900 used)
DAW : Ableton Intro (free)/Reaper (R600 licensed)
Mic stand : Hercules (R220)
Cable (generic R60)
Headphones : Sennheiser HD380 Pro (R1420)
Technically the 'phones were a gift many moons ago - but I approximated their cost at the time.