Adding a spiral staircase?

[fappyheet.livejournal.com]

Several properties around here own spiral staircases and I'm considering one to replace a rickety wooden version. One person I know suggested using a kit to build my own, but my time doesn't really allow for the process of a) DIY or b) doing it well.

Has anyone used a contractor to build their own stairs, either as a custom job or from a kit? I'm looking at the stairs themselves plus first and second floor landings. It'd be great to know of companies that did a great job or even those to avoid.

UPDATE: This is for outdoor use and would replace an external wooden staircase.