While you can use a Yahoo or Gmail as a free or paid email service for your personal email, there are many advantages to consider for a professional email service.
Best option is to have your email hosted on your website domain, so with every email, you are communicating your website identity to your customers, building your company image, and it looks very professional. That is why I would recommend irIST personal or business email service.
Features that add value to a professional email service are security mailbox, strong spam or virus protection and data encryption, ability to access your emails from a multitude of devices large email storage … etc.
Other desirable features, that most email service providers can satisfy are large or even unlimited storage, because a company email will be getting a high number of emails that will require ample storage, local servers (at least on the same continent), or even custom software applications that can provide additional value to the service.