Need help

Ok guys sorry for the long post but I need some help. In short my main question is going to be how many plants I should run under 4 x 1000w?

My last grow I used 3 lights the room was 8x12 with 8ft ceilings 6 plants and I pulled 3 1/2 pounds I didn’t think that was bad until I talked to the guy I bought the equipment from and he said he was getting 2+ per light so if that’s right I pulled half what he was pulling with the same equipment. Will co2 make that big of a difference he does run co2 I did a couple exhale bags

Now my current room is 14x18 with 10 ft ceilings 4 x 1000w lights how many plants should I run?

he also told me to make the room smaller to a 12x12 with 4 lights I also have a mini split and Dehumidifier so temp and humid are not a problem

Thank you everyone in advance

I would reduce the room size to 12x12 and run 20-36 plants, depends how long you want to veg. Remember to leave yourself access lanes so you can tend to the girls.

Honestly I think he’s trying to steer me in the wrong direction. He told me one plant per light so if I did that how long would I have to veg

With 1 per light you could veg for 8 weeks plus. I’d do 6 per light with 4 weeks veg. That should get you plants about 2.5’-3’ across and 3 feet heigh by the end. Depends on your skill level and medium too.