If you have everything you need to know prepared and have done the required pre-work like ensuring database access and such, then it can take an hour to a few hours, depending on the number of servers and what you're installing (blackpearl, smartforms, control pack, etc.)

Additionally to this some previous experience/exposure to the K2 Architecture will be very useful. Who will think a broen home page  means the application is installed and working fine =(

There are some gaps in the installation documentation, that mislead very easily if without any knowledge attempt to install.

Similar to Sharepoint, the Pre-Reqs are the most important and time consuming task, since depends on Windows Updates and ultimately your bandwidth.

K2 Installation with the appropiate accounts will also become easier if the documentation establish which tasks are performed, as what user. and also if truly walk you trough a real installation.  They have the room open for error, and give you the opportunity to configure as your wish, however they don't establish some best practices or recommendations in single box install. The absence of definition if everything goes into one application pool or within the same web app leave room for mis-interpretation and eventually perform a not perfect install.

Additionally they don't really cover the part of the binding and SSL even es fairly trivial, would be nice to have a full documentation/by example from scratch of a K2 Installation. that will shorten the time specially when integrating with Sharepoint 2013.

Last thing on the install. beware of the documentation, they don't mention some possible web.config changes to make all work properly, neither they mention on the Sharepoint Installation the need to copy and run from the root of the Sharepoint Plugin.

Hello, 

I made a developer installation without Sharepoint integration and Reporting Services, and it took no more than 3 hours, incluiding SQL installation and IIS. I only waited to get the license for the Smartforms.

Thanks!