I just finished a $1000 trial campaign. Being generous I will say I got 10 calls (probably only 2). At $100 per call and zero booking it was a huge loss for us! I have other lead sources that generate lots of leads and sales with the exact same ad verbiage. Shop around, be patient, and you will find a cost effective site to place ads on. My newest trial site cost $100 for the 1st month and has already brought in $2000 in the 1st week!