A genuinely useful AMC covers more than just one trade — plumbing, electrical, AC and general carpentry should all sit under the same agreement, so a building owner isn't juggling five different contractors for five different problems.
Scheduled inspections matter as much as reactive callouts. A good AMC includes a fixed number of preventive visits per year, catching small issues — a slow leak, a loose fitting — before they become expensive repairs.
Response time should be written into the agreement, not left vague. Ask what the guaranteed callout window is for urgent issues versus routine requests before signing anything.