Material: Stainless steel tanks (SUS304 or SUS316) are standard for durability. "Shinny" or stainless outer covers typically cost KSh 5,000 more than white/galvanized options.Technology:Evacuated Tubes: Most efficient in colder/cloudy areas like Nairobi or Limuru.Flat Plate: Extremely durable and often preferred for aesthetics; high-end models like Megasun or Kastom use this.Borehole Compatibility: If you have salty water, look for models specifically tagged as "borehole compatible" (often using plastic-lined tanks or high-grade SUS316 steel) like certain Seven SS Stars variants.