Comment on solar panels for sale by RLobato.
Were you looking at YouTube? There are a nmeubr of good videos there just search for solar water heater . These will not lay out every detail, it’s still assumed that you have the basic design skills to figure out how to put various sizes of pipes together, build a wooden box, etc.If you mean photovoltaic (solar electric) panels, there basically isn’t a cost-effective way to make good ones. There are various scams on the internet implying that you can do so don’t waste your money. If it were practical and cheap, the knowhow would spread like wildfire, and you would see houses everywhere with homemade panels.