so you've got a 4'x8' closet with a hatch to that attic?? yes, that is absolutely perfect for your first grow lol. you got like $700 so you could fabricate the closet quite well and smell would definitely be no issue.
shopping list:
-
orca grow film - trust me, get this not shitty 4ml thick mylar or something like that.
-6" inline fan+carbon filter combo
-ducting
-some 1 gallon smart pots and some 3 gallon smart pots
-i run 2 400ws in my bedroom closet, it's up to you though
-t5 light for veg stage is a good idea
that is a good list i would suggest to get started.