When sourcing garden lanterns, the IP (Ingress Protection) Rating is the most critical factor; ensure a minimum of IP44 for sheltered areas and IP65 or higher for exposed locations to guarantee resistance against dust and water. For solar-powered models, prioritize monocrystalline silicon solar panels for higher conversion efficiency and Lithium Iron Phosphate (LiFePO4) batteries for a longer lifespan (typically 2,000+ charge cycles). If selecting metal lanterns, ensure they are treated with anti-corrosion powder coating or made of 304 stainless steel to prevent rusting in humid environments.