Internal Developer Portals (IDPs) are essential for modernizing software development life cycles by consolidating tools and workflows, simplifying metrics, and standardizing ownership to enhance engineering efficiency. Selecting the right portal involves deciding between in-house development, customizing open-source tools, or partnering with vendors, each with its own trade-offs. A well-constructed Request for Proposal (RFP) is crucial as it aligns stakeholders, clarifies organizational goals, and ensures the focus is on real needs rather than outdated problems. A good RFP is concise, structured, use-case driven, and collaborative, serving as a decision-making tool to facilitate meaningful vendor discussions and avoid superficial comparisons. As organizations evaluate RFP responses, they should prioritize real use cases, vendor interaction, and the product's adaptability to future needs. A customizable RFP template can streamline the process, ensuring that teams ask pertinent questions and make informed decisions for selecting a developer portal that aligns with their organizational needs and fosters cultural and technical transformation.