| 4, Castle Street, Builth Wells | Freehold | 171 m² | £70,000 (2012) |
| 6, Castle Street, Builth Wells | Freehold | 76 m² | £115,000 (2018) |
| 8 Castle Street, Builth Wells | Freehold | 240 m² | £137,500 (2025) |
| 10 Castle Street, Builth Wells | Freehold | 170 m² | £220,000 (2025) |
| 12, Castle Street, Builth Wells | Freehold | 162 m² | £140,000 (2017) |
| 16 Castle Street, Builth Wells | Freehold | 94 m² | £210,000 (2026) |
| 17A, Castle Street, Builth Wells | - | 37 m² | - |
| 17B, Castle Street, Builth Wells | - | 45 m² | - |
| 17C, Castle Street, Builth Wells | - | 41 m² | - |
| 18 Castle Street, Builth Wells | Freehold | 128 m² | £140,000 (2025) |
| 20, Castle Street, Builth Wells | Freehold | 89 m² | £143,000 (2021) |
| 22 Castle Street, Builth Wells | Freehold | 77 m² | £145,000 (2022) |
| 23, Castle Street, Builth Wells | Freehold | 99 m² | £115,000 (2012) |
| 24, Castle Street, Builth Wells | Freehold | 81 m² | £178,000 (2023) |
| 25, Castle Street, Builth Wells | Freehold | 132 m² | £145,000 (2017) |
| 26 Castle Street, Builth Wells | Freehold | 58 m² | £170,000 (2022) |
| 26A Castle Street, Builth Wells | Freehold | 58 m² | £167,000 (2022) |
| 27, Castle Street, Builth Wells | Freehold | 113 m² | £170,000 (2024) |
| 28, Castle Street, Builth Wells | Freehold | 83 m² | £215,000 (2021) |
| 31 Castle Street, Builth Wells | - | 95 m² | - |
| 32 Castle Street, Builth Wells, Builth Wells | Freehold | 78 m² | £195,000 (2021) |
| 34 Castle Street, Builth Wells | - | 73 m² | - |
| Basement Flat, 13 Castle Street, Castle Street, Builth Wells | Leasehold | 44 m² | £58,500 (2020) |
| Flat 1, 15 Castle Street, Builth Wells, Builth Wells | - | 57 m² | - |
| Flat 2, 13 Castle Street, Builth Wells | - | 44 m² | - |
| Flat 2, 15, Castle Street, Builth Wells | - | 45 m² | - |
| Flat 3, 13, Castle Street, Builth Wells | - | 49 m² | - |
| Flat 3, 15, Castle Street, Builth Wells | - | 49 m² | - |
| Flat 4, 15, Castle Street, Builth Wells | - | 46 m² | - |
| Flat 4, 17 Castle Street, Builth Wells | - | 88 m² | - |
| The Courthouse, 33 Castle Street, Builth Wells | Freehold | 239 m² | £300,000 (2022) |