0 Harness St, Spring Valley, California 91977

Rare double-lot development opportunity in Spring Valley — APNs 578-102-14-00 and 578-102-15-00 sold together. Two contiguous parcels create a flexible canvas for builders, investors, and end-users navigating today’s California housing landscape. Under current 2026 state law, the development potential is significant: build two single-family residences (up to ~3, 000 sqft each), plus the potential for ADUs and Junior ADUs on each lot per California’s expanded ADU statutes. SB-9 lot-split and duplex provisions may further unlock additional units, subject to County of San Diego zoning and verification.