They are available as both kit (LulzBot KITTAZ 3D) and assembled (LulzBot TAZ 3D). The Lulzbot Taz is fully open hardware and open software so all parts can be downloaded directly from Lulzbot as well as all the mechanical drawings needed to produce the metal parts too (assuming you have access to a metal shop which I don't) as well as BOMs needed. You could manufacture a Taz without paying anything to Lulzbot. I don't have the resources to do that yet and I don't mind supporting a company that is willing to make EVERYTHING about their printer open and free should you wish it.

As a first printer, I thought it wise to go with assembled (mostly) to get up and running with the fewest issues. After that, I can use it to produce parts for other printers/devices or additional Taz if I want to expand my printer stable. I also have a 50w laser cutter/engraver that I can produce any laser cut MDF/Plexi/plywood parts for other printers with or additional components for the Taz (such as a plexi enclosure).

With the two machines (Taz and Laser), I have machines capable of creating/depositing material as well as removing/cutting material. From there, I can go lots of places. Including OpenSLS as I have a laser machine very much like the ones they used in their project. So that will give me SLS ability as well.

I have done considerable research and have been shopping for a printer for almost 3 years. I had settled on the Hyrel 3d for its ability to take up to 4 extruders and some of its interesting extruding options (clay, playdough, sugro,etc) but that advantage has faded as those types of extruders can be obtained now for use with virtually any printer. Back then, the earlier versions of Taz were in the running too. And on top of that I waited for over a year for availability of the Hyrel to come to fruition, in vein. I gave up and restarted from the beginning. The Taz quickly floated to the top along with the Ultimaker 2. But the Taz seemed to eek out a win on many things I considered important (filament types, multiple extrusion, build volume, ease of customizing, open source hardware/software, customer reviews, and company attitude in the industry).