A contentious question that is hard to answer. In general, the cleaner you keep your panels the more yield you will receive from the solar panels, the cleaner the surface and less dirt and or dust or debris on the panel the greater power that the panel is able to produce. Panels are within reason self-cleaning, If a panel has a relative pitch then the general weather conditions will offer a reasonable amount of cleaning, it won’t clean the backed on or hard to remove dirt and pollen but will clean most basic dust on a regular basis when it rains. Most installers and or companies suggest that every year or every second year is a good timeframe to get your panels cleaned. The only thing to note is that it costs money most of the time to get your panels cleaned and you need to make sure that the cost of the cleaning doesn’t out way the benefit of cleaning the panels.

In general no. Most of the major components can be set and forget items. Solar panels may need to be cleaned but will function without fault if they are never touched. Most solar railing systems will only need to be touched if they are close the salt water and corrosion accrues or extra panels are required. Solar inverters nowadays are mainly made in a fashion that if anything ever goes wrong with the inverter it will require a replacement inverter to be installed or a service technician and no attention from the client will be needed for this as well. I general check-up of the system is advisable roughly every 3 years in conjunction with letters that some DNS (electrical distributers) send out advising that its good to make sure your system is safe and that all components are in good working condition.