Hi, I'm not sure if you saw the current version of the ureka idea that is at ureka.org or if you saw the original version that was built on completely different technology and had very different features.

The current version of ureka is based on the version of the breakaway community code for Hive that is a cut down version of the code that runs ecency.com. That code is open source and you can set up a server that runs it for very litte or potentially for free. The current version is quite basic and not so simple to customise - so you would really end up with a Hive powered website that is oriented around a specific Hive community.

The old version of Ureka had a lot more features because it was based on the open source social networking framework at elgg.org. It had a built in chat system and many other things that Hive generally doesn't have. I am about to publish a blog post that provides a high level design for a future veresion of Hive that bridges some of the gaps involved here.

The cost and affordability is always unique to the project as it depends on what features you want to include and what avenues you have to generate income from the site. The potential spectrum of cost for a year's running is quite large.. It could be anywhere from a few thousand dollars to a few million ;)