yo you said 1 question and u just asked 3 lol.

yea the smell can get kinda bad if u have few females. if u cant afford a ventilation system(more for professional and commercial growers), then just put incense, or open a window.

cheap lights SUCKS. like 100w lights or halogen is the worst thing. your plant will just fuckin grow and get thiny and will sucks. they dont have the right spectrum. so the thing is to get MH, HPS, or a bulb. i guess thats it

dunno for the HID thing sry