For a mini-split system, or central heat pump? Do you have existing ducts? What's the square footage?
We recently upgraded our central heat pump as the old one died after 15 years or so. IIRC the total was $13k CAD, so around 9-10k USD, which included indoor and outdoor units for a roughly 3000sqft house, with installation. But all the ducting was there already, so it was just a matter of swapping out old unit for new. (Got some nice government grants too, so it was only a few k out of pocket.)