Physical Appearance or IT Certification: Which is more Influential to Customers?

For the most part what your are saying is right. In the residential market, appearance matters, especially once you meet face to face.

However, certifications will draw way more customers on the commercial side of things. When a small biz SEO runs a search for someone to setup a Windows 2008 server, he will be more persuaded if he say a Microsoft cert.

If an end user needed a Cisco router configured and installed he would be assured to see a CCNA or CCNP technician doing the job.

I believe certifications are an extension of your appearance. It is not something you throw in people faces. But a certification will show that you have some substance to go along with your neat appearance.