So I have been doing some research and I'm still sticking with my $1000 budget, but I have come up with a few contenders.
some criteria
freefloat
1:7 or 1:8 twist
16in barrel or longer

Radical Firearms RF 16" 5.56 SOCOM COMPLETE RIFLE WITH 12" FGS ROUND RAIL
http://www.radicalfirearms.com/product-p/fr16-5.56soc-12fgs.htm

Anderson Manufacturing AM15-M4 16 in Free Float rail with Magpul stock

OR build one ( complete upper and complete lower for around $700)
with a Primary Arms 5X Prism Scope with Patented .223/5.56, 5.45x39, .308 ACSS Reticle

what do y'all think? or any other recommendations?

What are you wanting to do with this rifle?  The complete upper you linked to isn't really what most would be thinking of for a precision rifle.

I would say a precision is going to start at 18" at minimum and more likely live in the 20-24' range to be truly effective.  It's also going to be heavy.  Maybe look at a used Stag 3G or Model 6?  DPMS makes some stuff that might fit your bill.  Either way I'd start at 18" uppers with 1:8, maybe 1:7 if you don't plan on shooting light varmint loads.  24" can get by with 1:9 up to 77SMK's (at least mine does) but will not handle AMAX loads.

Stick to your $1000 budget instead of the $700. Better parts will make your first time experience of owning a ar more enjoyable. You do get what you pay for.

Jp chrome lined barrels
Jp silent capture spring
Adjustable gas block
Troy industries/ Daniel Defense hand guards
Maybe a two stage trigger?
Troy industries front and rear flip up sights

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Most precision builds are around $2k
A good platform to copy for a precision build would be the M110
It all depends on what you want to do with the gun once your finished. That that will help guide you to starting your first build.

I would look at a white oaks armament barrel if your going to build your own along with maybe a larue or midwest industries rail.  I have had good luck with aero precision lowers and the set screw that comes with them helps to make a tight fit between the lower and upper.

Colt OEM 1
B5 systems SOPMOD stock
Daniel Defense Omega rail or any other rail you prefer choose.

Great reliable rifle and the civilian equal of what's issued to the troops. You can use a standard M4 handguard until you can afford something better.

If you ever wear the barrel out by a replacement 16" SPR profile from White Oak Armament for around $300 delivered after being blasted to a matte finish.