We want an AR before prices go too crazy. Little experience w/ARs so guidance is really appreciated.  It will be used for possible 3-gun, carbine classes, unlikely home defense (sev. pistols in home), and of course SHTF. Unlikely we'll shoot beyond 100yds. No hunting.

I'm mechanically inclined but not ready to buy tools for from-scratch build so will assemble complete upper and lower. Can I do that with common tools? I have a vise.

Trying for a little better than base model, budget ~$700, hopefully cheaper.  

I'm OK with PSA and blemished is fine. I get PSA daily emails and live In SC with a PSA store in town. Have looked at & read good things about Aero Precision too.

UPPER
Mid-length Gas System, 16"
Premium Barrel. Or, will PSA's Stainless Freedom do just as well? Would we even notice a difference?
Free-float handguard. Magpul, MOE or Keymod? Is there a difference between them as to mounting options?
And, it seems that if I want (I do) a free-float handguard I'll need an upper that comes with one because it takes special tools to install one?
The only one in stock is
[URL=http://bit.ly/2fkMCqe[/URL]

LOWER
Better trigger than basic. EPT or better.
The only premium lowers that list EPT or Defender triggers are out of stock so no idea of their price as PSA doesn't list it. What is their usual price?
Do those premium lowers regularly come back in stock (in-stock notifier is set) or do I look elsewhere for a comparable complete lower?
Stock - She's short w/short arms. I have long arms. We need plenty of length adjustment. Advice?

BCG/CH
Premium, Full-auto HPT/MI.
Not a big price diff. btw the basic and premium so why not?

MBUS Rear Sight.
Based on most of the PSA Upper pics it looks like they have a picatinny rear rail for the the sight?

Am I forgetting anything? Suggestions on product choices are VERY welcome.

Thanks!

1. Get the premium barrel if you don't mind the price. Their CHF premium barrels are one of the best.
2. Mlok all the way
3. I like the EPT triggger.
4. Assembling upper to lowers requires no tool. Slap them on and push two pins and it's done in 10 seconds with time to spare.
5. Full auto bcg lasts a little longer
6. The one in your link already has free float handguard
7. Blemish lower is what I like. Milspec lowers make no difference except for cosmetics
8. Adjustment are made with collapsible stock. You can choose their MOE complete lowers as they are nicer than the basics.
9. In ARs, upper or lower doesn't matter much as long as they are milspec.  The barrel is No. 1.  bcg and trigger are also important

The rest really don't matter.