Research Methodology and Data Sources

Breadcrumb: Nampa / Research / Methodology

Page type: Methodology
Published: 2026-05-05
Last updated: 2026-05-05

Summary: Nampa market intelligence is built on a five-tier source hierarchy—government data first, MLS second, broker reports third, surveys fourth, operator analysis last—with every metric tagged by confidence level, update cadence, and geographic scope to ensure institutional-grade reliability.

Source Hierarchy

All Nampa market data follows a strict five-tier hierarchy. Higher tiers override lower tiers when sources conflict.

Tier 1: Government & Official Records

Authority: City of Nampa, Canyon County, State of Idaho, U.S. Census Bureau, U.S. Treasury.

Examples:

• City of Nampa Zoning Code (Title 10)
• Canyon County Assessor parcel data
• U.S. Census Bureau American Community Survey (ACS)
• Idaho Legislature session laws (SB 1352, SB 1354)
• U.S. Treasury CDFI Fund Opportunity Zone designations

Update cadence: Ordinances update on effective date. Census data updates annually (ACS 1-Year) or every 10 years (Decennial). Assessor data updates quarterly.

Confidence level: VERIFIED.

Geographic scope: City limits for municipal code. County-wide for assessor. State-wide for legislation. National for Census.

Primary sources:

• City of Nampa Zoning Code — Municipal code library
• City of Nampa Planning & Zoning — Official planning department
• Canyon County Assessor — Property records
• U.S. Census Bureau API — Population and demographic data
• Idaho Legislature — Session laws and statutes
• U.S. Treasury CDFI Fund — Opportunity Zone designations

Tier 2: MLS & Public Market Data

Authority: Intermountain MLS (IMLS), Redfin, Zillow, Realtor.com, CoStar (multifamily).

Examples:

• Median sale price
• Days on market
• Active listings count
• Price per square foot
• Sold-to-list ratio

Update cadence: Monthly for aggregated metrics. Daily for active listings.

Confidence level: VERIFIED (for closed sales), ESTIMATED (for active listings and projections).

Geographic scope: City of Nampa unless otherwise noted. Some sources report Canyon County aggregate—always labeled.

Primary sources:

• Redfin Nampa Housing Market — Monthly market reports
• Zillow Nampa Home Values — Home value index
• Realtor.com Nampa Market — Inventory and rental data
• CoStar — Multifamily cap rates and NOI (subscription required)

Tier 3: Broker & Industry Reports

Authority: Regional brokerages, title companies, lenders, COMPASS (regional planning).

Examples:

• COMPASS population projections
• 375 Loan Ada vs. Canyon market reports
• Local brokerage market summaries

Update cadence: Quarterly or annually.

Confidence level: ESTIMATED. Broker reports often blend MLS data with proprietary analysis—always cite the underlying MLS source when available.

Geographic scope: Treasure Valley (COMPASS), Canyon County (375 Loan), or city-specific.

Primary sources:

• COMPASS Idaho — Regional population and growth projections
• 375 Loan Market Reports — Ada vs. Canyon County comparisons
• Local brokerage reports (cited individually when used)

Tier 4: Surveys & Third-Party Aggregators

Authority: NARPM (rental surveys), AirDNA (STR data), third-party aggregators.

Examples:

• Median 3BR rent (NARPM survey)
• STR occupancy rates (AirDNA)
• Rental yield estimates (third-party calculators)

Update cadence: Quarterly (NARPM), monthly (AirDNA).

Confidence level: ESTIMATED. Survey data reflects reported responses, not verified transactions.

Geographic scope: Metro or county-wide. Rarely city-specific for Nampa.

Primary sources:

• NARPM Treasure Valley Chapter — Rental rate surveys (member access)
• AirDNA — Short-term rental performance data (subscription required)

Tier 5: Operator Analysis & Renew Internal

Authority: Renew Group underwriting, broker experience, operator interpretation.

Examples:

• "Renew take:" commentary
• Underwriting assumptions (cap rate floors, rehab cost per sq ft)
• Market positioning statements

Update cadence: Continuous. Updated as market conditions shift.

Confidence level: OPERATOR. Clearly labeled as interpretation, not fact.

Geographic scope: Nampa-specific unless noted.

Disclosure: All operator analysis is labeled "Renew take:" in body text and tagged [RENEW_TAKE] in source annotations. Never presented as verified fact.

Confidence Levels

Every metric on this site carries one of four confidence tags:

Metrics without a confidence tag default to ESTIMATED.

Update Cadence by Data Type

All data-bearing pages display a "Last updated" date in the header.

Geographic Scope Definitions

Nampa market data uses four geographic scopes. Always check the scope label on each metric.

When a metric reports Canyon County but the page context is Nampa, the scope is explicitly labeled: "Canyon County (includes Nampa)."

Ordinance Citation Standards

All zoning and ordinance references follow this format:

Citation format:
[Ordinance name] [Code section] — [Brief description] (Effective [date])

Example:
Nampa City Code Title 10, Chapter 8 (RS Single-Family Residential District) — Accessory dwelling unit standards at §10-8-5 (Effective June 18, 2025)

Required elements:

1. Full ordinance name (Nampa City Code Title X)
2. Specific code section (§10-8-5)
3. Effective date (not adoption date—effective date)
4. Official source URL (City of Nampa or Municode)

Disclaimer (required on all ordinance pages):
"This summary is for informational purposes only and does not constitute legal advice. Verify current standards at [official source URL] before any development decision. Consult a licensed attorney for legal interpretation."

State Law (Shared Across Treasure Valley)

Three Idaho statutes apply to all Treasure Valley cities, including Nampa:

1. Idaho SB 1352 — Starter-home density allowance (Effective July 1, 2026). Local jurisdictions may not block starter-home density on qualifying parcels. Idaho Legislature

2. Idaho SB 1354 — Related housing-supply statute (Effective July 1, 2026). Idaho Legislature

3. Idaho Code §67-6539 — STR preemption. Cities may regulate but not prohibit short-term rentals. Idaho Legislature

These are cited in asset-class and deep-guide pages but not re-explained in every brief.

Metric Annotation Standards

Every metric in a research brief or asset-class page includes:

1. Value — The number.
2. Source name — Redfin, U.S. Census, City of Nampa, etc.
3. Date or period — March 2026, Q1 2026, ACS 2023, etc.
4. Geographic scope — City, county, metro, neighborhood.
5. Confidence level — VERIFIED, ESTIMATED, OPERATOR, or DATED.

Example (inline citation):
"Nampa's median sale price reached $418,000 in March 2026, up 1.6% year-over-year (Redfin, city of Nampa, March 2026, VERIFIED)."

Example (stat card annotation):

value: $418,000
label: Median sale price
source: Redfin
date: March 2026
scope: City of Nampa
confidence: VERIFIED
change: +1.6% YoY

Renew Internal Analysis Standards

All operator interpretation is labeled "Renew take:" at the start of the paragraph and tagged [RENEW_TAKE] in source annotations.

Example:
"Renew take: Nampa flips pencil at 15% gross margin in current conditions, assuming $50/sq ft rehab and 60-day hold. This assumes entry at $380K and ARV at $430K based on March 2026 comps. [RENEW_TAKE]"

Renew analysis is NEVER presented as verified fact. It is clearly separated from sourced data.

Data Gaps & Verification Flags

When a metric cannot be sourced, the page emits a verification flag:

Format:
``

Example:
``

Verification flags are resolved before publication. No page goes live with unresolved flags.

Sources

All sources cited in Nampa market intelligence:

Government & Official Records:

• City of Nampa Zoning Code — Municipal code library (Accessed May 2026)
• City of Nampa Planning & Zoning — Official planning department (Accessed May 2026)
• Canyon County Assessor — Property records (Accessed May 2026)
• U.S. Census Bureau — Population and demographic data (Accessed May 2026)
• Idaho Legislature — Session laws and statutes (Accessed May 2026)
• U.S. Treasury CDFI Fund — Opportunity Zone designations (Accessed May 2026)

MLS & Public Market Data:

• Redfin Nampa Housing Market — Monthly market reports (Accessed May 2026)
• Zillow Nampa Home Values — Home value index (Accessed May 2026)
• Realtor.com Nampa Market — Inventory and rental data (Accessed May 2026)

Broker & Industry Reports:

• COMPASS Idaho — Regional population and growth projections (Accessed May 2026)
• 375 Loan Market Reports — Ada vs. Canyon County comparisons (Accessed May 2026)

Methodology reference:

• Boise Methodology — Shared Treasure Valley methodology standards

Navigation

← Back to Nampa Research

Related pages:

• Nampa Investment Hub
• Boise Methodology — Shared Treasure Valley standards

change_type: created
change_summary: "Initial publication of Nampa research methodology page."
editor_name: "Renew"
change_date: 2026-05-05