SQL Server pricing is not a simple matter of a single price. It's a complex system that depends on several factors. Microsoft offers various editions, each with different features and capabilities. The pricing model is often based on core features, storage capacity, and the number of concurrent users. For example, the Express edition is free for development and testing, but has limitations on storage and users. The Enterprise edition, on the other hand, offers the most comprehensive features and scalability but comes with a higher price tag. Choosing the right edition is crucial for avoiding unexpected costs. It's essential to carefully consider your database size, expected user load, and the specific features you need before making a decision. Different licensing models, such as perpetual licenses and subscription-based models, also influence the cost structure. Understanding these nuances is vital for effective budget planning and resource allocation within a project.