Many do. Some owners part of Weed High Maintenance shirt maintenance concerns. Some do part of their own maintenance. Some airlines do maintenance for other airlines. Perhaps you can look up HAECO, operating in Hong Kong. Maintenance is required before the aircraft takes off again. The aircraft may not be at its home, the airline does not have any mechanical or equipment on site. There maintenance is performed periodically.
I believe they are called check A, check B and check C. Airlines can perform simpler checks in the Weed High Maintenance shirt house and ask the contractors to do bigger things. Also, I think you have a financial relationship between being on campus and outdated university budgets – universities often make up for their budget deficits with profits (often quite small). they earn from housing and eating. Many universities will have to charge more for basic tuition if they don’t want to do anything from expensive pieces of school infrastructure.
This here: Weed High Maintenance shirt