While it's true that content is key, it's also important to have the right content. You want people browsing the web to find what they are looking for on your site. They have probably looked in other places, and they may keep looking some after your site. But if they have found exactly what they want on your site, chances are they will come back and contact you.
So what are they looking for? Well, think about what you want to know when you're shopping. You want to find good quality products and services at an affordable price. So tell them what you can offer, and how much it is going to cost. Also, emphasize the value of what you are offering by explaining how it is better than what others are offering.
Let people know what you can do for them. Keep this in mind when you are writing, and you will develop content with great quality!