Need a database interface

Hi, I own a property brokerage company. I am looking to create a WP site that has a database to manage my clients/suppliers in real-time directly from the site. I considered Joomla, but was advised against it. Instead, people have directed me to WP. Are there any good WP themes or plugins that I could use to create a database of my clients and suppliers? I appreciate any feedback you can provide. I want the site to be as dynamic and professional as possible while still having a sort of database interface.

David