GIFV linkI am a bot . bot <| sep |> I find a common mistake is focusing in module selection while ignoring the inverter system racking attachments structural engineering installation process . To me , it doesn ' t make sense to select a premium module , adding a couple thousand dollars to project cost , only to have ugly conduit runs all over the building , an errorprone inverter that might not meet code requirements , no structural engineering evaluation , poor water sealing of the racking , and workmen tromping around on the shingle roof at the hottest times of day which damages the shingles . The solar module is the most reliable system component . If anything , it ' s the single line item that can be squeezed in terms of price .