HPS question

I am looking at a 400w High Efficiency HPS 50k lumens system comes with 21k temp light bulb, ballast, light timer, light reflector, and yoyo hang kit, for $150.
I know I will need another bulb for vegging, but with this set up how many plants can I handle? I will be growing in a closet the closet is about average size about 4ft by 7ft tall.

I think I could put about 10x 1gal pots in there.

4ftx 4ft area... make sure you watch those temps.. closets can get very hot with lights

i dunno what to tell you about yield or plant numbers...but if you go with that light kit...if it has a magnetic ballast...get a phillips ceramic metal halide..they run off 400w magnetic ballasts, have a much better spectrum then hps, lose less lumens over time, and are cheaper then hps bulbs, if you want a separate bulb for veg..that would be the best choice. I would actualy use it for flower too though. 150$ for that sounds like a great deal though.

*edit I thought 1000w hps's have a 4x4 footprint..I always figured a 400w would be more like 2.5x 2.5

Heat was something I was worried about. What about CFL's? Would it be wiser for a CFL grow inside of a closet then growing HPS?

Also could the 400w HPS handle 5-10 plants in a closet size space?

if heat is an issue the cfl's would be best. if not there are dual spectrum bulbs that are a hps/mh hybrid. you get best of both!!!
i think it would handle 5 but that would be about it unless you can lollipoip or sog it!!

10 cfls would cover that are quite nicely. 65w cfls at 2700k are 15$ at home depot. that 650w for 150$ and the combined lumens is 42,000. then you gotta figure the reflector for 7$ each plus socket extension(i had to use them, you might not) so add another 80$ and 10-20$ for a surge protector for all those plugs. so about 250 without tax. they will be much cooler than the hps, without a cooltube that is, and you can get 8" away so your plant will have way more lumens per sq inch by about 5 times opposed to a 400w hps 4ft away

5 3gal pots for 400w. 9 2gal pots

you can grow anything under that light in a 4/4 room. my thought is as you grow and you begin to see different growths in each plant rotate them under the light. king of turning then clockwise in the room. this will allow for even growth and it doesn't take much to turn them. doing this you wll be happy

Sounds good to me.