Brand New....Please HELP ME!!!!

Okay, I want to start some children in a small space in my rental. I have done my homework and I have decided to go with a 4-plant DWC hydroponics system and 5-gallon buckets with 6 inch net pot/lids, a high-output 4 outlet adjustable flow airpump with 8 inch airstones for each pot. I plan on using something like a Growlab tent that is 2'x2'x5'11". The only question is the lighting....this is where I need some help. I really want a 400w HPS system (something like a SunSystem setup or one of those Digital Greenhouse setups on HTG Supply), but I have a limited budget. I can get some more stuff in like a month (maybe), so should I maybe go with a T5 flouro and then buy the hps, or should I bite the bullet and get the hps? Or should I go with a 250w hps (really don't want to do that, if everything goes as planned, I want another one of these with a MH setup for vegging to keep it going all the time). I know I need somekind of exhaust, plan on using some sort of 4"-6" inline fan attached to my ducting and a homemade carbon scrubber (just got a really good idea using one of those indoor dryer vents and some activated charcoal). As far as the nutrient setup, I plan on using the lucas method using GH Micro and Flora (seems idiot proof, ph buffered and reasonably priced; as I get better and get the funds, I'll branch out to other supplementals). I'm going to be growing some decent bag seeds to get the feel of things before I spend the money and order some. Also, maybe a little help on where to get some. I live inside the U.S. and have considered Attitude Seedbank. Okay, that's just about it. I've got about a week before I can go out and buy all this shit, so hopefully someone will get back to me.

Wow you posted this 4 months ago and im just now seeing....well? what did you end up doing?