Based on your numbers, it's $700 sans OS. I'm missing the cost of the case as well. Though I guess with the right comparison in place, I'm still looking at about 800-1000 based on how much "upgrading" I want to do. I'd probably want to have a wifi module for it as well and the cost of arctic silver.
The problem still lies in the fact I'd have to put the thing together. Which means I'd instead likely have a stack of parts for (maybe) over a month.
Granting, building it has advantages aesthetically, cost effectiveness etc.
Main weakness being my issue with applying arctic silver (youtube can fix this), time to build (A weekend), RMA if needed (crossing fingers may deal with this)
Of course, this is based on current numbers. Black friday or Boxing day numbers would likely be different.
Yeah, I said it's roughly $700 sans OS/case in the last paragraph of my post. They're rough estimates based on the trends I've seen on parts pricing on Newegg.
You can get a decent wi-fi attachment from Newegg for about $25. Grab a Rosewill one that has good ratings.
You should be fine using the CPU's stock fan. AFAIK, all of Intel's processors come with one, and they come with thermal paste already applied. So just put it on and clip it down. I assume you won't be overclocking like an enthusiast.
If you insist on using your own paste, it's pretty easy. Just squeeze out a drop of paste the approximate size of a grain of rice onto the middle of the proc, and then push down on it the same way you'd push a piece of paper onto some glue on another piece of paper.
Can't help you with putting it together. Maybe you can pay a friend $40 to do it or something. Or, if you bring it up here, I can do that too, if you time it right.