Cabinet Grow Setup

Doing TONS of research due to the fact I'm planning on starting my first grow. I figure reading up on everything before I do it will allow me to identify problems before they arise and will make me the most efficient as possible on a first grow (: The more i learn the more i want to learn and questions keep popping up in my head haha

I've figured out I am able to grow in my best friends aunts house (as long as I give her some of the finished product haha) shes given me a 4x4 space to work with in one of the bedrooms. I'd like to keep it as short as possible so that im not bringing in a 4x4 box thats 7 feet tall and making her re think it but i am willing to make it as tall as it needs to be to make it work the best.

Ive been looking at hid/hps with a cool tube i also would like to possibly do a scrog grow since I've researched it and with my desire to keep it low and also it seems like it yields better in such a small area.

**** now for some questions (: ****

1) With proper ventilation and a cool tube will i be able to get an HPS /HID in this space without too many heat issues if the outside of the room is kept to 70-75 degrees? and how far off the canopy would i need to keep the light?

2) Is scrog too hard for a first time grower to accomplish? I've researched it only a little and it seems pretty straight forward but its an "advanced technique" so i am a little skeptical.

3) If scrog is too advanced is there enough room to do a conventional grow with a strain like white widow which grows to 3 ft a cab 6ft or less? If not can anyone who has grown the auto flowering types (especially auto ak47 by lowlife seeds) attest to their potency and if they would recommend them to a first time grower.

4) How many plants can i make fit in this space using either scrog and conventional growing techniques?

5) Should i go with a 400w/600w/1000w for this set up? I would like to only get one light at this point to save some $ and cause i doubt that a cabinet could take the heat of 2 hps even with cool tubes (:

Thank you all very much!!!!