1. It needs to be a laptop.

2. Thanks for everyone's help

3. Should I get a used or new laptop? I can get a really nice used one or a decent new one. (At least, that's just what I figure)

Well, it depends on do you want used one? i'd more likely to go with new one.

Anyways i did some re-search and found pretty dope deal from ebay if you are interested.
Alienware 17 R3 i7-6700HQ 8GB RAM 1TB HDD 1080P FHD GTX970M 3GB gaming

Very good deal, I'd buy that if it is still available.
Don't get used ones, you don't know if it has any flaws or bad ownership before.

I would take a look at this; I am ordering this for myself in September. See what you think.

http://www.pcspecialist.co.uk/notebooks/7981/

I will have more RAM, bigger SSD and no OS to come with it as a few changes.
Other changes too.

This is a huge laptop, very sturdy, metal body, 17.3" if you want a big screen. If you just wanted it to be portable in the sense that you would like to be able to pick it up and move it and have it in a backpack for wherever you move houses often or want to double it up as a machine you take out. I think it might be for you.

Of course if you're not going to buy it anytime soon, I can let you know first hand what I think of it come September; I've done a lot of research into it. (I'm also getting a ASUS x205ta for under 200 bucks as it has 14 hours of battery life, good for programming and word processing. Look into that and perhaps get a desktop instead of a gaming machine if you want it portable for work)