Commercial real estate underwriting: a buyer's reference
Self storage underwriting software: the Reddit question, answered
The choice comes down to three shapes: a spreadsheet built around a unit mix table, a general commercial real estate underwriting tool that supports storage as a property type, or a lease-by-lease valuation platform built for office and retail. The two valuation platforms we checked do not name self storage on the pages we read. Street rate and occupancy data is sold separately from whatever builds the cash flow. Decide the model shape first, then buy data to feed it.
What this page is, plainly
- People append "reddit" to this search because they want an answer from someone with nothing to sell.
- Altyst published this page, and Altyst sells commercial real estate underwriting software. So we do have something to sell.
- We did not read Reddit. We quote no post, no user, no thread and no vote count. Nothing below reports what anyone on Reddit said.
- Here is the straight answer anyway, with every claim about a named product taken from the vendor page we opened and linked at the bottom.
Why a multifamily model fits storage badly
The rent roll is a matrix, not a list
A multifamily rent roll lists similar things: unit, tenant, rent, lease end. A storage rent roll is a grid of size by type. A 10x10 drive-up, a 10x10 interior and a 10x10 climate controlled unit are three products at three rates. Average them and every rate assumption downstream is wrong.
There is no rollover schedule
Storage tenancies are typically month to month, which deletes what a lease-by-lease platform exists to run: rollover dates, renewal probability, tenant improvements, leasing commissions, expense recoveries. In their place you need churn and a lease-up curve.
ECRI is a second rent engine
Existing customer rate increases move a tenant's rent independently of the street rate. New customers arrive at today's asking rate, less any move-in discount; tenured customers absorb whatever increases the operator puts through. Rent runs on two engines: the street rate that sets the entry price, and the increase schedule that lifts the in-place base. In-place rent can sit above or below street rent, and one blended growth assumption matches neither. That cell is where a generic model quietly breaks.
Physical and economic occupancy are different tests
Physical occupancy is occupied units, or square feet, over the total. Economic occupancy is collected revenue over gross potential rent, which is the scheduled rent for every unit including the vacant ones, at a stated base. It is not unit count times average in-place rent; that version buries the vacancy loss in the denominator. The base decides the answer: measured against street rate, a facility whose tenured rents sit above street rate can show economic occupancy above physical, while against in-place rates concessions and bad debt pull it below.
Expansion pads are a second project
A storage deal may come with excess land, a slab, or entitlements for another building. That is a development pro forma inside an acquisition model: construction budget, timing, its own lease-up curve, its own stabilised NOI on top of the existing facility. A multifamily template has nowhere to put it, so it ends up bolted on below the cash flow, outside the sources and uses.
A storage checklist for your own spreadsheet
None of this needs our product or anyone else's.
- Unit mix table: size, type (drive-up, interior, climate controlled), count, rentable square feet, street rate, in-place rate, occupied units.
- Two rent engines per unit type: street rate for move-ins, an increase schedule for the existing base.
- Churn as move-outs per month, and occupancy tracked per unit type rather than blended.
- Gross potential rent as the scheduled rent for every unit including the vacant ones, at a base you label.
- Vacancy, concessions and bad debt as separate lines, never netted.
- Other income per occupied unit per month, since protection plans and late fees follow units, not square feet.
- Expenses from the trailing twelve, normalised, with taxes at post-sale assessed value where reassessment applies.
- NOI is effective gross income minus operating expenses, and debt service is not in it. State whether your NOI is before or after capital reserves, because DSCR, debt yield and cap rate all move with that line.
- DSCR is NOI divided by annual debt service; debt yield is NOI divided by the loan amount. Size against both plus LTV and take the smallest loan the three produce.
- IRR on unlevered and levered cash flow, equity multiple as total distributions divided by equity invested.
- The expansion pad as its own block: cost, timing, lease-up, the NOI it adds, funded from the same equity.
The options, honestly
A spreadsheet
For one deal a spreadsheet is usually enough. The unit mix grid is native to it and ECRI is a few extra columns. The costs arrive later: no audit trail, version drift across emailed copies, and broken references that can return a plausible wrong number rather than an error.
Lease-by-lease valuation platforms
Altus Group describes ARGUS Enterprise as "a comprehensive commercial property valuation software solution that covers cash flow forecasting, and asset management", says it is "now part of ARGUS Intelligence Platform", and states that "Pricing is flexible, tiered and scales with your business", by quote. The lease types it advertises modelling are "office, industrial, retail, multifamily, etc."; storage is not named on that page.
Rockport calls Rockport VAL "the future of commercial real estate cash flow modeling and valuation" and lists "office, retail, industrial, multifamily, hospitality, and mixed-use properties", which does not include storage. It advertises the ability to "Import ARGUS® exports" and publishes no price on the pages we read. Both are lease-based cash flow engines, and neither page names storage among the property types it models.
Self storage data platforms
These sell the inputs rather than the model. Radius+ presents itself as "The Industry's Most Comprehensive Market Intelligence Platform" and advertises "Unit-Level pricing, updated daily"; its products page describes a partner product, saying "Cactus, in partnership with Radius+, provides integrated financial underwriting, analytics, and data-driven insights". TractIQ says it carries "Achieved rates and full P&Ls", with "Revenue, expenses, NOI and NOI margin, line by line, for 4,000+ facilities nationwide" and "verified facility-level occupancy on $50B+ of assets, updated monthly since 2017". Neither publishes a price on the pages we read.
Operations software is not underwriting software
Storable's site lists Software, Websites, Access, Marketplace, Insurance, Collections and CRM, and names Storable Edge, Sitelink and Storable Easy among its facility management products. Nothing on the page we read mentions acquisitions underwriting, investment modelling or financial modelling.
Altyst, which is us
Altyst reads an offering memorandum, rent roll, trailing twelve, lease or a pasted listing link, extracts the figures, and builds an editable model: rent roll, T-12 normalisation, growth, vacancy, lease rollover with TI and leasing commissions, debt sizing, equity waterfall, DCF, IRR, equity multiple, DSCR, cash-on-cash, exit assumptions, scenarios and sensitivity tables. The AI does extraction only; the arithmetic runs on a deterministic CRE engine, so the same inputs give the same numbers and every figure traces to a source document or an assumption you can edit. Self storage is among the property types, exports are Excel, PDF and PowerPoint, and pricing is $12 a month for 5 deals, $24 for 15 deals, and $99 for a team of 5 seats at 75 deals. No free tier, no free trial.
The limits: it is a general CRE engine that supports storage, not a unit-mix-first storage product; it sells no rate or comp data; and it cannot open or produce ARGUS files. Free without an account are ten calculators, a 55-term glossary and a ten-year multifamily acquisition model in Excel.
What the vendor pages actually said
| Product | What its page says it is | Storage named on the page we read | Price published there |
|---|---|---|---|
| ARGUS Enterprise (Altus Group) | Valuation and cash flow forecasting; part of ARGUS Intelligence Platform | No | No, by quote |
| Rockport VAL | CRE cash flow modelling and valuation; imports ARGUS exports | No | No |
| Radius+ | Storage market intelligence; unit-level pricing updated daily | Yes | No |
| TractIQ | Storage occupancy data, achieved rates and full P&Ls | Yes | No |
| Storable | Storage operations: management software, access, collections, CRM | Yes | No |
| Altyst (ours) | CRE underwriting from documents, editable deterministic model | Yes | Yes, $12 / $24 / $99 |
Questions people actually ask
Can I just use a multifamily template?
You can start from one, but replace the rent engine: drop the single rent growth assumption, add a unit mix table with street and in-place rates by size and type, add an increase schedule for the existing base, and swap lease expiry logic for monthly churn. Keep the blended rent line and the model looks right and is wrong.
What is the difference between physical and economic occupancy here?
Physical occupancy is occupied units or square feet over the total. Economic occupancy is collected revenue over gross potential rent, which prices every unit including the vacant ones at a stated base. Because storage rents drift from street rate with tenure, the two can sit apart in either direction.
How do I model ECRI without per-tenant detail?
Split each unit type's occupied base into tenure buckets, apply the increase to a bucket at your assumed interval, and let move-outs empty the older buckets first. Three or four buckets per unit type keeps the schedule readable and auditable.
Do I need ARGUS to underwrite storage?
The Altus Group page we read advertises modelling "office, industrial, retail, multifamily, etc." and does not name storage. Nothing says you cannot build a storage model in it. If a lender asks for an ARGUS file, that is a workflow requirement, not a modelling one.
Where do street rates and comps come from?
From data vendors, not modelling software. Radius+ and TractIQ both sell facility-level storage data and neither publishes a price on the pages we read, so you have to ask. You can also collect asking rates by hand from competitor websites, which is slow, free, and what the vendors automate.
Sources
Every third-party claim above comes from one of these pages, opened on 16 September 2026. Pages we could not retrieve are cited nowhere.