I once had a room that wasn't getting proper ventilation and the girls would take forever to grow to size. I added CO2 and cut the time in half. I could tell the difference the day after I started. As far as spending $50 to $100 a week, I've never had that. I do believe that the only time it was worth the cash I did spend was in the that bad veg room. I never noticed a big enough difference in my bloom rooms. I think basements are the best places to grow. Good luck with your room!