The only "hard" part of the hardware is properly installing the CPU cooler.
As for software, you want to make sure after Windows is installed to apply the motherboard drivers from the motherboard support site etc.
$180 is pretty typical if you want someone to put it together for you.
Time to build:
It's going to vary. Probably a few HOURS when you factor in doing some preliminary reading, driver download installs, and of course Microsoft Updates take a while though that's automatic.
*The MOTHERBOARD MANUAL is an important thing to read for DDR3 memory placement and other tips.
**Linus' from Tech Tips and others have some good Youtube videos if you want to:
a) Learn how to install a CPU cooler
b) Watch a PC get built...