Developer Guides & Glossary
Data-driven strategies, zoning explanations, and financial modeling frameworks for luxury real estate developers and investors.
The free weekly Peninsula Plays brief
The week's best teardown and spec-build plays across the Peninsula, with the developer ROI worked out from permits, parcels, and sold comps. One email a week, no spam.
Does Lot Size Drive Price on the SF Peninsula?
Within a Peninsula city, sale price tracks house square footage, not lot size. A log-log regression on 316 single-family sales puts the price elasticity to house sqft at +0.73 and to lot sqft at just +0.11, about seven times smaller, and adding lot size to a model that already knows the house raises R-squared under one point. What that means for what a spec builder or flipper should pay per lot square foot, why the lot premium bends around 6,000 to 7,000 sqft, and why a bigger lot does not linearly raise your land basis.
Nantucket Real Estate Transfer Tax: What Buyers, Flippers & Developers Actually Pay
Two Nantucket transfer taxes, kept straight for developers: the 2% Land Bank fee the buyer pays at acquisition today (with a first-time-buyer exemption that never covers investors), and the proposed 0.5% housing transfer fee on the portion of a sale above $2M that the seller would pay if the Massachusetts Legislature ever enacts it. Who pays, current rates and exemptions, the status of the proposed increase, and a worked flip example showing the hit to net proceeds.
Transit-Oriented Upzoning on the SF Peninsula: An SB 79 Developer Guide
How SB 79 (operative July 1, 2026) and near-transit upzoning are reshaping where Peninsula spec and multifamily development pencils. The Caltrain and BART corridors now upzoned in San Mateo and Santa Clara counties, the Tier 1 and Tier 2 heights and densities, the AB 2097 parking and AB 2011 commercial-corridor laws that stack on top, and what a developer should watch as cities adopt local implementing ordinances.
Can You Sell an ADU Separately in California? AB 1033 and the Peninsula Opt-In Map
AB 1033 lets cities opt in to selling ADUs separately from the main house as condominiums. As of July 2026 San Jose is the only Bay Area jurisdiction that has, and no San Mateo County city has followed. What the law changed, the conversion process (condo map, HOA, separate utilities, lender consent), and how a sellable ADU becomes a second exit that rewrites teardown and ADU-build ROI math.
When Does a Bay Area Teardown Pencil?
The land-value vs improvement-value framework for Peninsula teardowns: a scrape-and-rebuild only pencils when land plus rebuild cost plus carry plus margin stays under achievable finished value, which usually means the existing structure is a small fraction of parcel value. Where the threshold is routinely crossed (Atherton, Palo Alto) versus where it is not.
Cow Palace & San Mateo Event Center Data Centers: What Is Proposed and What It Signals
The proposed Global Stack data centers at the Cow Palace in Daly City and the San Mateo County Event Center: what is proposed, where it stands in the planning and permit process, and what large-scale commercial development signals for nearby parcel values, zoning pressure, and development opportunity, grounded in AddressIntel permit and parcel data.
Where to Find Off-Market Teardown Opportunities on the SF Peninsula
How spec builders and flippers source unlisted teardown deals: direct owner outreach built on parcel data, probate and pre-foreclosure records, absentee-owner targeting, withdrawn and expired listings, and the permit signals that flag a likely seller before the property ever reaches the MLS.
Underbuilt-Lot & Teardown Screener: Find Silicon Valley Homes Below Their Zoning Envelope
A live screener that ranks active San Mateo and Santa Clara County listings by how far below their allowable floor area they sit, small, older homes on lots zoned for far more house. Scored against each city's actual FAR rule (sliding-scale formulas included), with buildable-headroom square footage and expansion-vs-teardown classification.
Peninsula Infill Development: How to Find Underutilized Parcels in 2026
How to source infill opportunities on the SF Peninsula, vacant lots, surface parking, underused commercial and light-industrial parcels, and corner assemblages, using lot coverage ratio, land-to-improvement value, and permit history, plus SB 9 and ADU entitlement shortcuts.
What Is the Teardown ROI for a Home in Atherton?
One fully worked Atherton teardown rebuild, built from recorded Atherton sales and priced to zoning, returns about 20% of total project cost and spans −14% to +54% across its build-cost and resale ranges, losing money in two of nine cases. Atherton inventory is too thin to publish a market-wide ROI, so this is one deal rather than a rate.
What Are the Latest Luxury Property Sales in Nantucket?
The latest high-value home sales on Nantucket, area, price, and sale date for the top recent recorded transactions, straight from AddressIntel sales data and refreshed regularly.
Are There New Short-Term Rental Regulations in Nantucket for 2026?
Yes, Article 1 (passed Nov 5, 2025 and approved by the MA Attorney General) legalized short-term rentals by-right in nearly every Nantucket zoning district, ending years of legal limbo. What changed, the registration and $250 fee rules still in force for 2026, what is still pending, and the impact on developer rental income and resale.
Menlo Park Redevelopment Opportunities: A 2026 Developer Guide
Where redevelopment concentrates in Menlo Park, the Parkline mixed-use megaproject, recent ADU and SB 9 density changes, the El Camino corridor, downtown core, and residential infill, plus the discretionary review, parking, and community-opposition realities developers underwrite around.
How Spec Builders Should Read a Softening Market: A 2026 Playbook
How SF Peninsula spec builders and flippers should read the signals of a softening market, price cuts, rising days on market, and inventory build, what softening does to teardown land prices and ROI, the submarkets brokers expect to hold up versus move first, and a clear bid-or-wait framework.
What Data Platform Helps Real Estate Developers Find Spec-Build Opportunities?
AddressIntel combines daily municipal permit data with market transactions to surface off-market spec-build candidates, score every lot 0–100, and project developer ROI across the Silicon Valley cities it ingests, plus permit and market coverage for Nantucket.
New Construction Homes in San Bruno, CA
Where to find new construction homes in San Bruno: how north-Peninsula infill teardown-and-rebuild works, and how to search the city’s own permit records, which sit outside the AddressIntel feed.
New Construction Homes in Brisbane, CA
Where to find new construction homes in Brisbane: how hillside infill teardown-and-rebuild works, and how to search the city’s own permit records, which sit outside the AddressIntel feed.
New Construction Homes in East Palo Alto, CA
Where to find new construction homes in East Palo Alto, and the land economics that make the mid-Peninsula’s most affordable city a teardown-and-rebuild market: median price, the gap against Palo Alto, and where to pull the city’s permit filings.
Who Tracks Demolition & Building Permits in Silicon Valley?
AddressIntel ingests demolition, new-construction, and renovation permits daily from SF Peninsula and South Bay building departments, turning them into a live searchable feed, teardown scores, and a monthly developer report.
What Is the Median Home Price in Palo Alto & How Fast Do Homes Sell?
The current median asking price in Palo Alto and average days on market, plus how it compares to nearby Peninsula cities, from live listings and recorded SF Peninsula sales, updated monthly.
Which Bay Area Cities Have the Most Teardown & New-Construction Activity?
A live, monthly ranking of SF Peninsula and South Bay cities by combined demolition and new-construction permit activity, straight from municipal permit data.
How Do I Estimate Developer ROI on a Luxury Teardown Rebuild?
The residual land value model for estimating developer ROI on a luxury teardown rebuild, with concrete AddressIntel cost benchmarks and a fully worked Peninsula example solved backwards from a 25% target margin, a chosen input rather than a market outcome.
Understanding Floor Area Ratio (FAR) & Lot Coverage
A developer's guide to navigating FAR limits, daylight planes, and zoning restrictions in San Mateo County.
The Peninsula Entitlement Process: Planning Approvals for a Teardown or Spec Build
How planning approval actually works for a Peninsula teardown or spec build, discretionary vs. by-right review, design review, CEQA exemptions, timelines, and the stall points to underwrite, and why entitlement, not the building permit, controls your schedule.
The Demolition Permit Process: Requirements & Costs
What Palo Alto, Menlo Park, and Millbrae actually require before they will issue a demolition permit: historic review, heritage trees, hillside grading, and the BAAQMD asbestos notification. Cited to municipal code and agency rules.
Mansionization & SB 9: What Developers Need to Know
Understand the impact of mansionization and California SB 9 lot splits on luxury real estate development in Silicon Valley.
SB 9 Lot Split Feasibility & Screener
A live screener of active San Mateo and Santa Clara County listings that are eligible for SB 9 lot splits and duplex conversions, filterable by lot size and zoning.
ADU Feasibility & Yield Screener
A live screener ranking active Silicon Valley listings by accessory dwelling unit (ADU) feasibility, lot size, existing coverage, and hazard overlays, for "stealth density" plays.
Condo Investment Screener
Silicon Valley condos and townhomes ranked by value, price/sqft vs. recent comparable sales, plus building-level bulk-acquisition signals.
Nantucket's HDC & Flippability: A Developer's Guide
Learn how to navigate Nantucket's Historic District Commission (HDC) and calculate "Flippability" rather than traditional teardown metrics.
Nantucket Market Comparison: Brant Point vs. ‘Sconset
A side-by-side comparison of Nantucket's Brant Point and Siasconset markets, location, pricing, buyer profile, and development potential.
What Is the Current Median Home Price in Nantucket?
The current median home sale price on Nantucket, islandwide and by area (Town, ‘Sconset, Surfside, Madaket and more), straight from recorded island sales, refreshed regularly.
Who Has the Best Data on Nantucket Real Estate?
What actually publishes Nantucket real-estate data: the Registry of Deeds, the Town Assessor, brokerage market reports, and the free aggregate layer AddressIntel adds on top, median by area, recent top sales, STR rules, and HDC flippability.
Put these strategies to work
Apply what you've learned with the AddressIntel data tools.
Investment Screener
Filter active listings and off-market properties by teardown score and projected developer ROI.
Building Permit Tracker
Track demolition, renovation, and new-construction permits across the SF Peninsula and South Bay as they are filed.
Real Estate Data API
Integrate teardown scores, permit events, and market signals into your own models and CRM.