This document provides recommendations for efficient in-building DAS networks. It discusses key topics such as estimating site traffic, selecting active or passive solutions based on capacity needs, designing for future technologies, validating coverage predictions, optimizing indoor and outdoor coverage, enabling multi-operator sharing, meeting requirements for VVIP sites, upgrading old systems, coordinating planning and design, and standardizing design documentation. The recommendations emphasize selecting passive solutions where possible, accurately estimating capacity needs, validating design tools with real-world testing, and coordinating across teams to optimize new and existing network deployments.