Help?

Hey guys long time reader (minimalist poster) I have a serious question for anyone who can help me with my situation. I don't have much space to grow as I live in a one bedroom apt with my gf so a small closet grow is pretty much my only option. I have a couple successful grows under my belt at my old house but this limited space is worrying me. My complex always lets me know in plenty of time before they come plus I want to limit this grow to as little equipment mess etc.(evidence) as possible. I have two main questions. I am only planning on using a self enclosed 150watt to flower with so heat and such won't be much of an issue. I have ordered 6 cataract kush seeds from DNA. I understand that ideally one wants to grow out all of them, sex them and flower all the females, all the while taking clones to determine a mother to keep. I don't really need a perpetual harvest just enough to get a oz a month or less for personals. Should i still go about this process considering that my space is very limited to do this or should I flower all the girls I have once they show their preflowers and hope for the best. I don't wanna grow crappy pheno's out but at the same time I don't know if I have space to select a mother.

Any help would be greatly appreciated and thank you in advanced. I have alot of respect for some of you guys and gals on here and I hope that you can help me figure out what to do cause i am stuck in my head right now