SkyMax Internet Marketing gives a great point and we try to do the same when its possible with our clients. I do want to build on that though.
You also have to keep this in mind. Out of the 100% of the searches for any given term you can expect an average of 20-30% of them to go for the PPC ads. The rest is broken up between the other channels mixed up in the universal search experience. That includes natural results, local, image, video, social, news, etc.. You should have all the tracking in place to make an educated decision as to whether or not its working for you. You can get Google Web Analytics for free and call tracking can be automatically tied into that via 3rd party vendors for a very reasonable price. Don't forget to setup your other success metrics too though.
Feel free to contact us and we can help evaluate your campaigns. bestlocalmarketing.com
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