We purchased the Original Prusa i3 MK3 Kit from Prusa Research by Josef Prusa www.prusa3d.com for 769 Euro and it took us about 10 hours to assemble it, from opening the package to starting the first print.
Here is a 15 minutes time-lapse video (fast forward 20x ~ 5 hours) showing the kit assembly.
Prusa Research provides Slic3r Prusa Edition (PE) and PrusaControl (build on top of Slic3r PE) as their slicer tools.
We use a 3D printing benchmark, a Treefrog, to compare the 3D prints of different filaments.