| Houses | Tank Price (US$) | Total Cost (US$) | Total Benefit (US$, for 20 years) | BCR | PBP (Year) |
| Type A | 2846 | 2992 | 2258 | 0.72 | 27.6 |
| Type B | 680 | 805 | 1330 | 1.65 | 12 |
| Type C | 300 | 425 | 834 | 1.95 | 10 |
| Type D | 295 | 420 | 810 | 1.92 | 10.1 |
| Type E | 294 | 419 | 960 | 2.28 | 8.7 |
| Type F | 136 | 261 | 600 | 2.22 | 9 |