Rheem furnaces typically range from around $850 for a basic unit up to over $4,000 for high-end models (equipment only), while total installation can bring the cost to about $2,500–$7,800 nationally. The exact price depends on factors like the furnace’s heating capacity (BTU output), whether it’s single-stage, two-stage, or modulating, and the product line (Classic, Classic Plus, or Prestige series).