| 1 Mayfair Court, Observer Drive, Watford, Watford | Leasehold | 65 m² | £240,000 (2006) |
| Flat 2, Mayfair Court, Observer Drive, Watford | Leasehold | 67 m² | £229,000 (2005) |
| Flat 3, Mayfair Court, Observer Drive, Watford | Leasehold | 75 m² | £335,000 (2022) |
| Flat 4 Mayfair Court, Observer Drive, Watford | Leasehold | 72 m² | £286,000 (2015) |
| Flat 5, Mayfair Court, Observer Drive, Watford | Leasehold | 70 m² | £240,000 (2013) |
| Flat 6 Mayfair Court, Observer Drive, Watford | Leasehold | 81 m² | £240,000 (2006) |
| Flat 7, Mayfair Court, Observer Drive, Watford | Leasehold | 76 m² | £235,000 (2011) |
| Flat 8 Mayfair Court, Observer Drive, Watford | Leasehold | 65 m² | £290,000 (2025) |
| Flat 9, Mayfair Court, Observer Drive, Watford | Leasehold | 65 m² | £246,000 (2013) |
| Flat 10, Mayfair Court, Watford | Leasehold | 66 m² | £340,000 (2024) |
| Flat 11, Mayfair Court, Observer Drive, Watford | Leasehold | 67 m² | £322,000 (2023) |
| Flat 13, Mayfair Court, Observer Drive, Watford | Leasehold | 73 m² | £337,000 (2018) |
| Flat 14, Mayfair Court, Observer Drive, Watford | Leasehold | 67 m² | £205,000 (2006) |
| Flat 16, Mayfair Court, Observer Drive, Watford | Leasehold | 72 m² | £235,000 (2013) |
| Flat 17, Mayfair Court, Observer Drive, Watford | Leasehold | 74 m² | £235,000 (2012) |
| Flat 18, Mayfair Court, Observer Drive, Watford | Leasehold | 68 m² | £332,000 (2020) |
| Flat 19, Mayfair Court, Observer Drive, Watford | Leasehold | 68 m² | £300,000 (2015) |
| Flat 20, Mayfair Court, Observer Drive, Watford | Leasehold | 68 m² | £209,995 (2006) |
| Flat 21, Mayfair Court, Observer Drive, Watford | Leasehold | 69 m² | £229,500 (2006) |
| Flat 22, Mayfair Court, Observer Drive, Watford | Leasehold | 80 m² | £242,500 (2006) |
| Flat 23 Mayfair Court, Observer Drive, Watford | Leasehold | 75 m² | £305,000 (2025) |
| Flat 24, Mayfair Court, Observer Drive, Watford | Leasehold | 78 m² | £340,000 (2025) |
| Flat 25 Mayfair Court, Observer Drive, Watford | Leasehold | 67 m² | £216,000 (2006) |
| Flat 26, Mayfair Court, Observer Drive, Watford | Leasehold | 67 m² | £247,000 (2007) |
| Flat 27 Mayfair Court, Observer Drive, Watford | Leasehold | 80 m² | £247,500 (2006) |
| Flat 28 Mayfair Court, Observer Drive, Watford | Leasehold | 68 m² | £320,000 (2021) |
| Flat 29, Mayfair Court, Observer Drive, Watford | Leasehold | 73 m² | £325,000 (2021) |
| Flat 30 Mayfair Court, Observer Drive, Watford | Leasehold | 57 m² | £229,500 (2006) |
