How to calculate it yourself
DIY material total = (sheets needed × sheet price) + 10% for mud, tape, and screws. Professional total = (ft² × $/ft² installed). Most pros quote a flat per-sheet price for hanging plus per-square-foot for finishing.
Common scenarios
Single 12×12 room (DIY materials only)
17 sheets at $14 = $238 + $50 for mud, tape, screws = ~$290 total materials.
Single 12×12 room (installed)
~530 ft² × $2.50 = $1,325 average installed cost. Cheaper rooms run $1,000; high-end finish work runs $1,800.
Whole-house re-drywall (1,800 ft² home)
About 5,500 ft² of drywall surface. Installed cost: $11,000–$19,000. Materials alone: ~$2,500.