As far as the Craig's List posting...
- las vegas craigslist > > create posting
Your posting will expire from the site in 45 days.
I am sure that you all know already about that and you'll join me in pursuing to have it changed.
The Craig's Admin personal have a criteria in evaluating the volume of ads per regions... Each state/city has an other period of time to post their listings.
- s.f. bayarea craigslist > > create posting
Your posting will expire from the site in 7 days. - washington, DC craigslist > > create posting
Your posting will expire from the site in 7 days. - sacramento craigslist > > create posting
Your posting will expire from the site in 7 days. - new york craigslist > > create posting
Your posting will expire from the site in 7 days.
To name only few... I am not clear how they do that but I am going to post to the admins on Craigslist Forum and inquire for a revision of Las Vegas posting duration. I believe that the more of us will raise the question the better.
For some of you, out there, who would like to get more exposure on Craigslist and post more freqvently your AD, you can go to Craigslist Forum: http://sfbay.craigslist.org/forums/?forumID=9 and raise the question.
There is a way to repost by deleting your post and repost it... but very often they flag your post and make further activity difficult (specially if you repost within 48 hours, over and over again the same content... someone will single you out). See previous post: Posting on Craig's list... every 48hours? Why to go around like this (even if it is legal) and attract suspicions when we could collectively change that by posting our request to Craig's Admin.

I know Craigs list is free... but is it really worth the time? I always post listings to it, and never have I received a direct call from the site.
Hmmmmmmmmmm - something to think about. Maybe it's just my local market :-)