Best thing i can get for 500$ ?

hello , im going to be saving up 500$ im almost there already what should i get ? hps , grow tent etc etc . . .

anyhelp im a new grower
i could upgrade some stuff but not right away .

http://www.htgsupply.com/Product-Digital-Greenhouse- 600w-HPS-Grow-Light.asp

i also set a budget of 500$ for my first legit grow and thats what i decided on, ill be growing vertical with it and using cfl for a mother in another room.