I 've been using craigslist for years now. I had someone do it for me.. but to be honest i think that you need more that 3 ads a day. I usually do more than 6 ads a day. remember that once you post an ad, there is a bunch of other postings.. so your ad goes down... the average person that views cl wont go beyond 2 page or more.. it also depends how competitive is your business market. What i did is created several emails accounts that are tag to different cl acct. and if you change your text around from each posting... they wont reject it. i also did the same thing for different states. I have a great return posting in cl.... the only thing is that for some reason when i post in my city (orl-fl).. i get a lot of call of people just shopping around.. other states have given me a better return.
I say you do it, you will than get a feel of what works for you..