then they feel like it
Generally there is a maintenance schedule with what is to be done, when to be done, who to do in any good standard industry. Maintenance crew generally follow the schedule.
An Equiptment Maintenance worksheet is a log to keep track of your equiptment. It is used to show when preventitive maintenance is done and needs done to keep equiptment running smooth
Aircraft service and maintenance is done in a Hangar. It is the resting place for a plane. It can also be done in an open field.
normally about 6 hours, but that maintenance is done
You should follow your maintenance reminder or maintenance schedule in your manual. So it depends.
The maintenance required light just means there is regular scheduled maintenance that needs to be done. Look in your owner's manual and it will tell you exactly what needs to be done. Can be just an Oil/Filter change. This applies to the Maintenance Required light and not to the Check Engine light.
Someone can use a condition based maintenance in many different ways. They can improve system reliability, decrease maintenance costs, and they can decrease the number of maintenance operations done by human hands.
Yes, painting is part of common area maintenance. This is done in cases of people moving out of apartments and such.
For major maintenance on planes that will move, you park the plane in a hangar. But if you're doing something fairly minor or the plane is unable to move (you went to the airport to fly your plane and found a flat tire), maintenance can be done when the plane's parked anywhere. A lot of maintenance is done to airliners when they're sitting at the gate between flights.
Cheaper labour
Most of them are done on a maintenance schedule or if there is a problem with them not firing. Check your local repair manual or servie maintenance manual.
At least twice a year