Comfort Systems USA Inc (FIX) is overvalued and Mastec Inc (MTZ) is slightly undervalued.
Against our estimates of intrinsic value, MTZ trades at the wider discount: a margin of safety of +8%, against -73% for FIX.
Values as of the 22 Sept 2026 close.
Discounting its cash flows at 12.3% (average of 3 methods) values the shares at $937.74; the price of $1625.13 is 73% above that value, and 68% of that value comes from beyond year five.
Leak Score 75/100 on 10 of 12 signals
Discounting its cash flows at 12.4% (average of 3 methods) values the shares at $240.05; the price of $221.69 is 8% below that value, and 67% of that value comes from beyond year five.
Leak Score 41/100 on 9 of 12 signals
| Metric | FIX | MTZ |
|---|---|---|
| Verdict | Overvalued | Slightly undervalued |
| Price | $1625.13 | $221.69 |
| Intrinsic value | $937.74 | $240.05 |
| Margin of safety | -73% | +8% |
| Leak Score | 75/100 (10/12) | 41/100 (9/12) |
| Market cap | $57.2B | $17.8B |
| Revenue growth, 5 years | 26.1% | 17.7% |
| Operating margin | 16.4% | 5.2% |
| Net margin | 12.8% | 3.1% |
| Return on equity | 55.3% | 15.4% |
| Debt to equity | 0.11 | 0.93 |
| P/E | 40.0x | 35.3x |
| Forward P/E | 27.0x | 17.6x |
| P/B | 17.8x | 5.0x |
| Dividend yield | 0.2% | — |