How do I calculate the total cost of a plumbing or HVAC job with markup?
The estimator follows standard contractor practice: it sums material, labor (hours x rate), permits, and disposal into a subtotal, applies markup as a percentage, then adds contingency on top, and finally applies tax. The expression is total = ((material + labor + permits + disposal) x (1 + markup%)) x (1 + contingency%) x (1 + tax%).