Assembly · the primary product · in active development

Build the work file with proof of every source.

Most appraisal software helps you fill in fields. North Star's Assembly does that — and witnesses every input. Engagement letters from your email, MLS pulls, sketch creation, in-field photos and notes — each one captured into the audit chain at the moment it enters the work file. When you sign off, the Decision Record proves end-to- end custody of every fact in the report.

Join the waitlist How the audit chain works

Why custodial assembly matters

Evaluate — our first-shipping product — runs your already-finished work file against 360+ rules and seals the evaluation. It's useful and it ships first. But the audit chain on a Evaluate can only attest what we observed at the moment you uploaded: this is the file you submitted, this is when, this is what the rules said. The work file's underlying accuracy is your professional judgment.

Assembly is what the audit chain was actually built for. When North Star helps build the work file, we see where every input came from: the engagement letter parsed from your inbox, the MLS comp pulled from the public records database, the front-exterior photo taken on your phone at 10:14 AM at the subject address, the sketch rendered from your tablet's measuring app. Each of those gets witnessed at the moment of capture. The final Decision Record carries end-to-end provenance for every field in the report.

For a regulator or attorney three years from now, that's the difference between “the appraiser said so” and “the cryptographic chain shows the source data, the inspection timestamp, and the transformations applied between them.” The seal earns its full weight in Assembly.

How Assembly works, end-to-end

Five custodial steps, each one witnessed into the audit chain. The work file is born inside North Star; the audit chain follows it from intake to delivery.

Engagement intake

Connect your business email account. When an engagement letter or order email arrives, North Star's intake agent extracts the assignment metadata — client identity, intended use, subject property, due date, fee structure — and shows you a draft work-file scaffold for review.

What's witnessed: the source email (message id, sender, received timestamp), the extraction's output, your acceptance of the extracted assignment. The hash of the original email lands in the chain so the source is provably identical to what you saw.

Source collection

The agent pulls the source data you'd otherwise chase manually: prior sale history from the county recorder, comparable sales from the MLS, FEMA flood- zone determination, zoning lookups, parcel maps, tax-assessor records. Each fetch is logged. You see what was retrieved, when, and from where.

What's witnessed: the source URL, the timestamp of the fetch, a hash of the retrieved data, and your review / approval of each item before it enters the work file. Disputed sources can be flagged with a per-item annotation that becomes part of the chain.

In-field inspection

On the inspection day, the North Star mobile app captures your photos, sketch, condition notes, and GPS-stamped check-in at the subject property. The app works offline; everything syncs to the audit chain when you're back in coverage.

What's witnessed: each photo (timestamp, GPS coordinates if you opt in, hash of the image bytes), each condition note (you and when you wrote it), the sketch (each measurement recorded), and your inspection-completion sign-off. Photo metadata is sealed so it can't be retouched after the fact.

Work-file assembly

Back at the desk, the work file is assembled from the witnessed sources. North Star surfaces every field's provenance — click "where did this come from?" on the GLA figure and you see the ANSI measurement, the date it was captured, and your sign-off. The narrative drafter (still requires human review and sign-off) drafts paragraphs that cite back to specific witnessed facts.

What's witnessed: every transformation (rounding, unit conversion, narrative draft, manual edit), every override you apply, every decision the system surfaces for your judgment. The work file's field-level provenance graph is sealed alongside the content itself.

Rule evaluation + sign-off

The completed work file runs against the same 360+ rule library you'd use in Evaluate. Findings get rendered with the same severity / citation / improvement structure. You resolve, override, or accept. When you sign off, North Star seals the final Decision Record — this time carrying not just the evaluation event but the entire custodial provenance chain.

What's witnessed: the same Evaluate evaluation event (content hash, rule-set, findings, timestamp), plus the chain of all prior witnessing from steps 1–4. The result is a Decision Record that's defensible at every layer, not just at the evaluation moment.

What the Assembly seal attests

In Evaluate, the Decision Record is an Evaluation Event Witness — it attests what we ran our rules against, when, and with what result. That's a real protection, but it's narrow on purpose because we didn't help create the content.

In Assembly, the Decision Record is also a Custodial Provenance Witness. Because we captured every source as it entered the work file, the seal attests substantially more about the underlying evidence:

What Assembly's seal additionally attests

The source of every input. Each data point in the work file links back to a witnessed source — an email, a database query, an in-field photo, a sketch measurement. The chain proves where the fact originated.
The timestamp of every input. Photos taken at 10:14 AM, an MLS comp pulled at 11:02 AM, a sketch finalized at 2:34 PM. Each capture moment is sealed with a third-party timestamp.
The transformations applied. Every rounding, unit conversion, narrative draft, manual edit, and override is logged with author + reason. The chain shows the path from raw input to final field.
Photo and sketch integrity. Photo EXIF metadata is sealed at capture so any later retouching breaks the seal. The sketch's measurement-by-measurement log shows it wasn't fabricated after the fact.
The chain-of-custody narrative. A regulator can ask "show me how you arrived at this GLA figure" and the chain produces the audit trail automatically — from measurement to final report.
The chain stays there when you need it. Assembly retains your work-file documents for 5 years from the assignment effective date — mirroring USPAP, WAC 308-125-210, and OAR 161-050 record-keeping obligations — plus an additional 2 years if you flag the case as the subject of judicial or regulatory proceedings. Sealed Decision Records survive indefinitely. Full retention policy →

What Assembly's seal still does not attest

That the valuation conclusion is correct. Even with end-to-end provenance, the value opinion is your professional judgment. The chain documents what you considered; it doesn't substitute for the analysis.
That you observed the property accurately. Photos prove what was captured; they don't prove your inspection notes are complete or your condition rating is right.
That third-party source data is accurate. If the MLS comp's reported sale price was wrong at source, the chain proves we retrieved that wrong figure — not that the figure is correct.
That the appraisal complies with rules outside our library. Same as Evaluate — the chain attests against the rule set in force at sign-off, not against any blanket standard.
Legal advice or professional opinion. Software, not judgment.

See the audit-chain page for the full framing across both products.

Start with Evaluate. Move to Assembly when it ships.

Assembly is the primary product. It's the version of North Star where the cryptographic seal carries its full weight, where the day-to-day workflow lives inside our platform, and where the custodial chain is the differentiator.

It is also in active development. The audit-chain primitives, the rule library, the engine, and the verification path all exist and are battle-tested today. The custodial-intake agent, the source-collection workflows, the mobile inspection app, and the field-level provenance graph are being built right now. We're not shipping vaporware; we're shipping Evaluate first because it lets us harden the infrastructure at customer scale before Assembly opens accounts.

The path forward:

Today: Join the waitlist. WA and OR appraisers get first access to Evaluate when their state opens.
Evaluate (shipping first): Run your existing work files through North Star, see findings, download sealed Decision Records, get familiar with the platform. Build trust at low operational risk.
Assembly (the destination): Open to Evaluate customers first as it stabilizes. Build new work files inside North Star with end-to-end custodial provenance.

Waitlist members hear about Assembly milestones first.

The trust story, in one paragraph

Most appraisal software is a glorified word processor. North Star is a custodial workflow with a tamper-evident record of every input. When you build a work file inside Assembly, the Decision Record at the end isn't just proof you submitted the file — it's proof you sourced the comparable from this MLS query at that timestamp, that you took the front-exterior photo at this location on that date, that you applied this adjustment for that reason. Three years from now, when a question comes in, the chain answers it without anyone needing to take anyone's word for it. That's the product North Star is built to become.

Be in line for Assembly access.

Evaluate customers get first access to Assembly when it opens. Join the waitlist today and you're in line for both.

Join the waitlist