maintenance
Companies contracted to keep objects, products, or properties in working order through upkeep or repair.
Maintenance firms are companies which are contracted to perform regular upkeep or repair services which keep objects, products, and properties in useful and working order.
The service concerns keeping an existing object usable or restoring its working condition. A particular repair can be part of this role alongside scheduled upkeep.
A construction firm builds or alters a structure, while a maintenance firm provides its upkeep. The same organization can perform different work on different projects.
