Your solar panels should be able to get a maximum amount of light form the sun. If you are set against hiring a professional to assist you, you can start tracking the sun's movements yourself to calculate the best positioning.
Demonstration of the difference between North and East-West panel and sunlight performance Full blog with results of our study can be found at …
Low prices can be very attractive but keep in mind that solar panels and their installation is not cheap. If a vendor has extremely low prices, you are probably getting low quality equipment or even second hand equipment. It is best to invest in quality solar panels and hire a trustworthy contractor to install them.
Cleaning your solar panels does not need to be labor intensive. You want to avoid abrasive soaps at all costs, as they can deteriorate and even destroy your panels. So long as there is not caked up dust or bird droppings, frequent rinses with just hose water should be more than enough.