Solar systems ordinarily do not require much maintenance. Solar panels are self-cleaning, however, if you feel that your panels do need a clean, there are plenty companies out there specialized in cleaning solar panels.
As there are no moving parts to a solar panel, there is no wear and tear, and most reliable solar panel manufacturers offer lengthy warranties. Therefore, after paying for the initial installation there is not much cost to maintenance.
It is no secret that with all things as amazing as solar, there are going to be some cons. One of these cons is that birds can be a nuisance, however we have the answer to issues like these. To deter birds from your panels we can install pigeon wire / bird mesh, this would be installed around your panels and therefore stop and block any birds from getting under your system.
Another con is that solar systems can take up a lot of space on your roof, as the more energy you want to produce, the bigger your system will have to be. This is because you will want to attain as much sunlight as possible. An alternative to using all the space on your roof is to install a ground mounted system, this tends to be a popular solution with many commercial builds.