Why it matters on your quote
In a ducted heat pump system, the outdoor unit connects to a coil inside the air handler, which may also hold electric backup heat strips. In an AC and furnace system, the furnace does the air handler's job and the coil sits on top of it.
The air handler must be matched to the outdoor unit: the efficiency rating on a quote belongs to that exact pair. A quote should list the air handler's model number, not just the outdoor unit.