How to evaluate real estate underwriting software

The demo is not the test

Every underwriting product looks capable in a demo, because the demo runs on a document the vendor chose. The offering memorandum is text-native, the rent roll has one row per unit and no merged cells, and the presenter knows which button to avoid. Nothing you learn there survives contact with a scanned T-12 that came out of a copier at an angle.

So the useful evaluation is not a feature checklist. It is twelve questions, asked of everyone, with your own deal package on the table.

The twelve questions

1. What actually computes the numbers?

Ask directly whether the financial results come from a deterministic calculation engine or from a language model, and then ask them to run the same deal twice and show you both results. If a returned IRR moves between two runs on identical inputs, nothing downstream of it can be audited: not the memo, not the committee deck, not the answer you give a lender.

Where Altyst lands: a deterministic engine in exact decimal arithmetic. AI reads documents and proposes values, and never performs the calculation. Same inputs, same result, every time.

2. Can you click a figure and see where it came from?

Not "we cite sources" as a category. Click a specific number, and ask what appears. A defensible answer names the document and shows you the text the figure was read from, tells you how sure it is, and reaches the exports rather than living only on screen.

Where Altyst lands: on screen, every extracted figure carries the document it came from, the excerpt it was read from, a confidence, and a page number when that excerpt can be placed on exactly one page. An excerpt that appears on several pages is left unpinned rather than guessed at, and a figure you typed yourself has nothing to trace. In the exported workbook there is a Provenance tab, and it works one level up: every driving assumption, whether it was your figure or a proposed one, what kind of source stands behind it, and how firm that source is.

3. What does it read, and what does it do when the page is a photograph?

Ask for the format list, then ask about the scanned page specifically. Ask what happens when the rent roll and the trailing statement disagree: whether the conflict is raised for a human to settle, or resolved quietly by whichever document was parsed last.

Where Altyst lands: PDF, Excel, CSV, Word, plain text and photos of a page, with OCR for scanned documents. Extracted values are proposed with a confidence for review, and documents are tied out against each other with conflicts raised to you.

4. Is the asset class model real, or a relabeled multifamily model?

The tell is the vocabulary. An office model that talks about units instead of leases, or a hotel model with no ADR and no departmental expenses, is a multifamily model wearing a hat. Ask to see lease-by-lease rollover on an office deal and departmental expenses on a hotel.

Where Altyst lands: multifamily and single-family, office and medical office, retail, industrial, flex and warehouse, self-storage, mixed-use, hotel and hospitality, land and development, redevelopment and adaptive reuse, and ground-up hotel development. Those run on four adapters built for four different income models: per-unit residential, lease-by-lease commercial, land and development carry, and a departmental hotel model on occupied room nights and ADR. Inside the commercial one, each class carries its own defaults and lease economics, so self-storage recovers no operating expenses and books no TI or leasing commissions while office recovers most of them and carries months of downtime. An office deal is not a multifamily model with the labels changed, but eight of those classes do share one lease-by-lease engine, and you should ask us to prove the difference on your own rent roll.

5. How does it size debt?

Three sizing tests decide most deals: loan to value, minimum debt service coverage, and debt yield. Ask which are supported, and whether the product tells you which constraint binds. Then ask about the structures you actually see: a mezzanine piece, an interest-only period, a bridge loan to a refinance.

Where Altyst lands: sizing on LTV, minimum DSCR, or debt yield, with mezzanine, interest-only, additional tranches, and bridge-to-refinance structures.

6. What does the rollover model carry?

For anything with commercial leases this is the whole model. Tenant improvements, leasing commissions, downtime between leases, renewal probability, and expense stops. A product that models expiries but not downtime overstates income on any deal with rollover inside the hold, because the months a suite sits empty never reduce anything.

Where Altyst lands: lease-by-lease rollover with TI, LC, downtime, renewal probability, and expense stops. Ask us the same follow-up you ask everyone: bring a rent roll with a messy expiry schedule and look at what the model does with it.

7. Is the waterfall real?

Ask for a preferred return that compounds, return of capital, a general partner catch-up, a residual promote, and multiple IRR hurdle tiers. Then ask what happens to a structure that does not fit, because something in your book will not fit.

Where Altyst lands: all of it, off by default. Structures outside that shape are a job for the exported workbook, which is the honest answer rather than a roadmap date.

8. Is after-tax an overlay or an afterthought?

If your investors care about after-tax returns, ask for depreciation on the correct schedule, recapture at sale, passive-loss carryforward, and a 1031 deferral, and ask whether the after-tax figures flow into the exports or only appear on one screen.

Where Altyst lands: an overlay covering straight-line depreciation, passive-loss carryforward, unrecaptured section 1250 gain plus capital gains at sale, and an optional 1031 deferral, on rates you supply. Bonus depreciation is in there too, and the cost-segregated slice it creates is treated as section 1245 property, so it recaptures at the ordinary rate rather than the section 1250 rate. The whole overlay is off until you turn it on, because a default tax rate is a wrong tax rate.

9. What comes out, and does the Excel contain formulas?

Ask for a sample export before you buy, and open it. A workbook of pasted values is a report. A workbook of live formulas is a model you can keep working in. Ask which tabs recalculate, and be suspicious of a vendor who does not know off the top of their head.

Where Altyst lands: an Excel workbook on live formulas, a one-page investment memo PDF, an editable PowerPoint deck, a deck PDF, a lender package, and an offering summary. Some workbook tabs are engine-computed values; the Cover tab names which tabs recalculate and says so plainly.

10. What happens if you leave?

Ask what you can take with you, in what format, and what happens to your deals after a cancellation. The good answer is that the exports are ordinary files and the work stays reachable.

Where Altyst lands: exports are files that open without us. After a cancellation the workspace, deals, models and exports stay accessible; only new paid processing pauses. Deleting a deal removes its documents and results and produces a receipt; deleting a workspace does the same across every deal in it, and its receipt names anything still pending.

11. What is the security posture, stated in specifics?

Ask for the subprocessor list by name, where documents are stored, whether uploads are used to train anyone's models, how deletion works, and which certifications they hold. On that last one, listen for the word "compliant", which is not an audit. A vendor with no certification who says so is more trustworthy than one implying an attestation they do not have.

Where Altyst lands: workspace isolation enforced server side, role-based access, encryption in transit and at rest, published subprocessors, documents never sold and never used to train third-party models, and no SOC 2, ISO 27001, or comparable certification. We say that last part on the Security page rather than leaving you to discover it in procurement.

12. What is the pricing shape, and what is metered?

The headline number matters less than the meter behind it. Ask what counts as a unit: a seat, a deal, a document, a run. Ask what happens when you hit a limit, whether unused capacity carries forward, and whether re-running a model costs anything.

Where Altyst lands: plans are Individual $12, Professional $24, Team $99 a month, with a stated per additional deal price and a published monthly ceiling on new deals for each plan. The unit is one deal creation. Recompute, edits and exports are never metered, and unused deal credits roll over. Details on Pricing.

A scorecard you can take to every vendor

Score each vendor on your own deal, not the demo file. The last three rows are the ones that get skipped in a demo and then decide the renewal.

Two things worth ruling a vendor out over

A number that changes between runs. If the same inputs produce a different IRR twice, the product cannot support an audit trail no matter what its marketing says about traceability. It costs you one repeat run to check, and it is the only item on this page you cannot be talked out of.

A refusal to show a sample export. The export is the handoff back to you. A vendor unwilling to send one before a contract is telling you something about what is in it.

Where this leaves us

Altyst is the kind of product that owns the model. That is a real cost to you: you do not get to keep your firm's template as the authoritative artifact, and if a structure falls outside the engine you finish it in the exported workbook. What you get for it is that the arithmetic is deterministic and testable, every extracted figure carries the document and the excerpt it was read from, and the same model shape comes out of every deal so the tenth one is comparable to the first.

If that trade is wrong for your firm, one of the tools that sits on top of your own spreadsheet is the better purchase, and you should go make that call quickly rather than sitting through six demos to arrive at it.