As far as seeds. would you buy your kid a ferarri for his 16th B-day? Same goes for Newb grows start with inexpensive seeds get your system worked out, then move up to the "elite".
CO2 all you need is good flo-thru ventilation. CO2 is very expensive to set up. You'll see online those "homeade yeast" things those things IMHO are a joke. but to me its not worth it the bucks for a good set-up. Good air circulation and lights, ferts, etc. is all you really need. I'll never have a CO2 setup. I grow fine without it. just my 2 cents.
Now breeders and commercial ops. would benefit from a good CO2 set-up, but then they are growing for Max. yeild for Max. bux.