Whilst many database and email server applications are free to download and implement, a 10-user and up networked office system requires careful planning and implementation. This is my speciality. The basics behind single user systems are usually straight forward but when you are looking at mass communication, it becomes a different kettle of fish. Backups and failover redundancy tasks require experience and knowledge.
Choosing the right tools for the job is vital. Even though there are many free and open source tools, this isn’t always the most sensible approach. Commercial tools can provide the expert with efficient and speedy answers to problems as can the experienced professional who knows what he’s doing.