Not some crazy Russian spambot.

Just finished building, looking at quotes for ducted air installation.
Anyone know anything?

We've had quotes ranging from

$8K for 2 zones, 12kW cooling/13kW heating to
$12k for 4 zones, 14kW cooling/16kW heating

We like the 4 zones as there's at least 1 room we'd like to separate in its own zone as we don't use it much.

Is the extra $4K gonna be worth it over 15-20years?