I flower in a walkin closet, and stealth is NOT an issue, although heat is. Keep that in mind.
In the flower closet I use a 400w Hortilux Eye with a cheap wing reflector. Other stuff I use, in a second.
Some good points were mentioned.
Lights on at night is good for those of us with temp issues. (5:30pm-5:30am for me)
Closet open during lights on, I tacked a heavy sheet type material on the
inside of the door frame for two reasons, one during lights on, it keeps the majority
of light from spilling out from under/around the door, second, during lights off it prevents light leaks into the dark closet. The material also breathes so the fans I run can do the job. The material can be propped from the inside to allow fresh air flow and still act as a light trap too.
Fans, I use 4 total. 1 12" honeywell hurricane type, 2 4" basically throwaway type fans you can sometimes buy for five dollars, but they last upwards of two years. These three fans run during the 12 hours my light is on. Last a 300cfm extraction fan four inch ducting. I only run the extractor fan for 15 minutes every 3 hours. The OP said holes were not an option, they weren't for me until I upgraded to 400w Hortilux bulb, so until I got that I extracted out the closet door.
My ambient room temp is 84-88 depending if the extractor is going.
Temps under my plants are not much of an issue do to fan placement and distance
from plant tops to light. I do have to water plant every three days, one of the big draw backs to higher temps. Leaves will crisp when plants are thirsty so very rarely do my leaves ever get too limp or too dry, if they do thats when they fry.
I've had to make small changes to combat heat issues since i'm not looking to upgrade lights but a perpetual grow with moderate equipment is doable in a closet.
I don't have a lot of pics of my flower room but a few of my current grow show the
basic idea, and the results so far this flower cycle.
The four plants range in age between first day female up to
four weeks female. Notice the bushy look of multi topped plants.
The grow space is 3 1/2' by 3' by 4' although I could grow from the floor doubling to
amount of height, no need to do that, my plants are for the most part under two and a half feet tall.
I should mention my electric bill runs between $90 in the winter to as high as $150 in the summer. My veg/clone closet uses cfls and at most a heating pad under my cloning dome so minimal electricity cost. With the extractor fan I have, when it runs the whole 12 hours of lights on, add $30-40 a month.