20 Sunnyside Ave — Sale in Mill Valley, CA
- Price: $5.2M
- Listing type: For sale
- Asset type: Office
- Location: Mill Valley, CA 94941
- Size: 7,300 SF
Photos

Investment Figures
- Price per square foot
- $712
Derived from the asking price and operating figures published for this listing. Informational only — not an appraisal, valuation or financial advice. Verify independently before relying on any figure.
Market Context
This office in Mill Valley, CA is listed for sale at $5,199,000 across 7,300 SF ($712/SF). Compare it against other office listings for sale in Mill Valley, CA — view the full market.
As of Q2 2026, the San Francisco office market showed a 26.8% vacancy rate, average asking rents near $71.41/SF/yr, and rents up 1.0% year over year. Source: multiple brokerage reports, Q2 2026.
Rising rents point to a competitive market where well-priced, well-located assets trade quickly.
Office market FAQ
- Is the San Francisco office market tightening or softening?
- Vacancy is around 26.8%, with asking rents rising year over year (Q2 2026).
Contact
- Brian Foster · +1 (415) 451-2437 · brian.foster@cushwake.com
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