Buyers should prioritize printing technology, typically choosing between Direct Thermal (no ink needed, cost-effective) and Thermal Transfer (more durable, requires ribbons). Key specs include Print Resolution (DPI), where 203 DPI is standard for text, but 300 DPI is necessary for small barcodes or logos. Additionally, verify Battery Capacity (mAh) to ensure it supports at least 4-6 hours of continuous operation, and check Connectivity options such as Bluetooth 5.0 or Wi-Fi for seamless mobile integration.