No, the difference in cost between central air conditioning (a heat pump that works in one direction) and a heat pump that works in both directions is negligable unless you're being ripped off.
Here’s a concrete example that took 5 minutes to find. Two condensers from the same company, same seller, same SEER, same series, same tonnage, except the second does heat. The heat pump is 29% more expensive.
2 Ton 14.3 SEER2 Trane Air Conditioner Condenser - RT Series. $1615
