Alameda County property records for 6 addresses on Onyx Ct, Castro Valley, CA · Last verified August 2026
| Properties | 6 |
|---|---|
| Median Sale Price | $605,000 |
| Deeds and Mortgages on File | 7 |
| Median Price per Sqft | $457 |
| Owner Occupied | 100% |
| Median Annual Tax Bill | $6,428 |
| Median Year Built | 1947 |
| Median Ownership Tenure | 18 years |
Owner names and prior sale amounts shown locked below are available instantly with a free trial.
3 bd · 2.5 ba · 1,984 sqft · built 1947 · 0.128 acres
| Last Sale | Tax Bill | Prior Sale | Owner | Records |
|---|---|---|---|---|
| $172,000Aug 1995 | $6,4282025 | —Aug 1995 | 1 Name on Record Owner Occupied | Assessor + 2 DocumentsUpdated Aug 2026 |
3 bd · 2 ba · 1,631 sqft · built 1947 · 0.128 acres
| Last Sale | Tax Bill | Prior Sale | Owner | Records |
|---|---|---|---|---|
| $2,9272025 | —Jun 2025 | 2 Names on Record Owner Occupied | AssessorUpdated Aug 2026 |
4 bd · 3 ba · 1,823 sqft · built 1947 · 0.144 acres
| Last Sale | Tax Bill | Prior Sale | Owner | Records |
|---|---|---|---|---|
| $1,370,000Mar 2024 | $17,3582025 | Amount on Record Jul 2020 | 2 Names on Record Owner Occupied | Assessor + 5 DocumentsUpdated Jul 2026 |
3 bd · 1 ba · 1,080 sqft · built 1947 · 0.144 acres
| Last Sale | Tax Bill | Prior Sale | Owner | Records |
|---|---|---|---|---|
| —Mar 2011 | $3,8432025 | —Oct 2002 | 1 Name on Record Owner Occupied | AssessorUpdated Aug 2026 |
3 bd · 1 ba · 1,322 sqft · built 1947 · 0.167 acres
| Last Sale | Tax Bill | Prior Sale | Owner | Records |
|---|---|---|---|---|
| $605,000Apr 2006 | $10,5422025 | —Apr 1994 | 1 Name on Record Owner Occupied | AssessorUpdated Oct 2025 |
3 bd · 1 ba · 1,080 sqft · built 1947 · 0.167 acres
| Last Sale | Tax Bill | Prior Sale | Owner | Records |
|---|---|---|---|---|
| $89,000May 2008 | $4,0402025 | —Aug 2005 | 1 Name on Record Owner Occupied | AssessorUpdated Oct 2025 |
Source: USDA Forest Service Wildfire Risk to Communities · 2nd edition (2024), fuels as of 2020
| Wildfire Risk | Not rated no burnable land in reach |
|---|---|
| Wildfire Likelihood | Negligible |
| Exposure | None beyond ember reach |