well your gonna need at least a 2'x3'x 6' "box" or cabinet....
then your lights and nutes, that alone (light and GOOD nutes) will run around 300 buck minimum (light/nutes/soil, etc....) then you got to "find" the grow box....Check out
Grainger Industrial Supply or
Quill.com Office Supplies, Furniture, Ink, Toner, Paper, Technology. you can find a "box" for around 200 bucks in there. Either way, ask around, i dont think you can "make" a setup for anything less than 500 bucks. but think of it this way, your first harvest, you get 3 ounces of DANK...thats 3 opunces times $ 480 .... well thats over 1300 bucks if you were to sell it off..... meaning you get a 200% return on your investment, the first time around..... or use the same figures there and thats how much ou just SAVED yourself. Either way, it pays for itself after your first harvest, so take the time and invest in a good system that will continually produce what you want. and if your really slick, you get yourself another cabinet about a month into the veg state of your older plants, and you clone them in another cabinet, so that every 2 onths your harvesting something, and this way if you clone a female, you will always have females, aka the bud producers.
hope this helps