Even when you're selling, a free bonus may be the thing to clinch the deal. That's who you're writing to. You're not writing for yourself. Your job is to convey benefits to the reader. All of your classified writing should tell the reader how they will benefit.
Good benefits sell better.
Sell them on how they will benefit, and you have your foot in the door. You can construct a powerful classified ad around them, and probably draw an audience. Good classified ads simply draw the potential customer into the full sales pitch, whether it be your website, autoresponder, or 800 number. A good classified arouses enough interest to request more information almost against their will . Now, be prepared to edit.