One of the wonderful things about solar panels is that there are no moving parts, and next to zero maintenance. A wipe, brush or spray down occasionally will help prevent any buildup of dust that can impact the effectiveness of the collection.
Our batteries require no greasing, tightening etc. Just use them. If you can store it plugged into the wall that is best. Not only does this keep the battery fresh, but it will always be ready to go when you are.
If it is being stored for long periods of non-use make sure you plug it in every 5 months to keep the battery in good health.
If the inverter gets wet just make sure the ports are dry before plugging in anything.
Bulbs are rated for 20,000 hours of use. Just dust them off to keep them nice and bright.