Your Spreadsheet Isn't an Underwriting Engine
Excel can calculate IRR. It can't model tenant lifecycles, recovery structures, or GP/LP waterfalls without hundreds of brittle formulas. Solsten replaces the spreadsheet with a purpose-built CRE platform — plus ML forecasting and Saga AI assistant.
Import your existing rent rolls and expense budgets directly from Excel. No rebuilding from scratch.
Why Spreadsheets Break CRE Underwriting
Formulas Break Silently
Insert a row, delete a column, copy a sheet — and formulas break without warning. One misplaced cell reference can throw off your entire underwriting by millions.
No Audit Trail
Who changed the cap rate last Tuesday? Which version has the right rent roll? Excel doesn't track changes, so you're left emailing "v3_FINAL_FINAL.xlsx" back and forth.
Rebuild Every Deal
Every new property means copying an old model, updating formulas, and hoping nothing breaks. Recovery structures, step increases, and waterfalls must be hand-coded each time.
Can't Scale Past 1 Person
Two people editing the same Excel file means merge conflicts, overwrites, and lost work. There's no real-time collaboration, permissions, or investor-level access control.
What Solsten Does That Spreadsheets Can't
Full Proforma Engine
Annual and monthly operating statements generated automatically from your inputs. No formulas to build, no references to maintain. IRR, NPV, cap rates, and NOI — computed instantly.
Recovery Modeling Built In
NNN, Base Year Stop, and Modified Gross recovery structures are first-class features — not custom formula hacks. Recoveries auto-link to operating expenses and update when expenses change.
ML-Powered Forecasting
Solsten learns from your actual payment history. Expense forecasts blend observed growth rates with your assumptions — getting smarter with every data point.
Saga AI Assistant (Beta)
Ask "Why did NOI drop in year 3?" and get an answer grounded in your actual property model. Saga explains assumptions, timelines, and outputs — no more reverse-engineering your own spreadsheet.
Time-Passage Intelligence
Open a property you modeled 6 months ago and everything is current. Leases expire, vacancies extend, market rates inflate — automatically. Your spreadsheet just shows stale numbers.
Team & Investor Access
Share properties with teammates. Give LPs a private dashboard showing their equity slice. Control who sees financing, investment terms, or audit logs — per property, per person.
Feature-by-Feature Comparison
An honest look at both approaches.
| Feature | Solsten | Excel |
|---|---|---|
| Annual Proforma Engine | ✅ | — |
| Monthly Proforma Engine | ✅ | — |
| Rent Roll Timeline with Projections | ✅ | — |
| NNN / Base Year Stop / Mod Gross Recoveries | ✅ | — |
| GP/LP Waterfall Modeling | ✅ | — |
| Multi-Loan Debt Service & Amortization | ✅ | — |
| Exit Scenario Analysis (Every Exit Year) | ✅ | — |
| ML-Powered Expense Forecasting | ✅ | — |
| AI Assistant Grounded in Your Property Data | ✅ | — |
| Automatic Time-Passage Intelligence | ✅ | — |
| Tenant Lifecycle Tracking & Projections | ✅ | — |
| 15-Factor Risk Scoring | ✅ | — |
| Built-In Audit Trail | ✅ | — |
| Cloud-Based Team Collaboration | ✅ | — |
| Organization & Investor Access Controls | ✅ | — |
| Portfolio Aggregation & LP Dashboards | ✅ | — |
| Vacancy Auto-Extension & Market Snapshots | ✅ | — |
| Inflation Engine (Day-Level Compound) | ✅ | — |
| Basic Financial Calculations (NPV, IRR) | ✅ | ✅ |
| Completely Free to Start | ✅ | ✅ |
| Total Formula Flexibility | — | ✅ |
| Universal Availability (Every Computer) | — | ✅ |
| No Learning Curve | — | ✅ |
| Starting Price | Free Beta | $0–$160/yr |
Where Spreadsheets Still Win
We believe in transparency. Spreadsheets have real advantages:
- • Total flexibility — You can model literally anything. Custom waterfalls, unique deal structures, one-off scenarios that no software anticipates.
- • Universal availability — Every computer has Excel or Google Sheets. No accounts to create, no logins to remember.
- • No learning curve — If you already know Excel, you can start immediately. No new interface to learn.
- • No vendor lock-in — Your data lives in files you control. No subscription to cancel, no data migration to worry about.
For quick back-of-napkin calculations or truly unique deal structures, spreadsheets are hard to beat. But for the 95% of underwriting that every CRE deal requires — proformas, recoveries, tenant timelines, waterfalls, risk scoring — Solsten eliminates the formula risk and gives you institutional-grade output in minutes.
Bring Your Existing Data — Don't Start Over
Already have rent rolls and expense budgets in Excel? Import them directly. No reformatting, no manual re-entry.
Export Your Data
Save your existing rent roll or expense budget as .xlsx from Excel or Google Sheets.
Upload to Solsten
Click "Import from Excel" on the Tenants or Expenses page. Our wizard auto-detects your columns — suite numbers, tenant names, dates, and amounts.
Review & Refine
Preview the mapped data, apply bulk defaults for recovery type and step increases, and fix any edge cases before importing.
Full Analysis — Instantly
Your data flows into the proforma engine. Get a complete operating statement, IRR, NOI, risk scores, and tenant timeline — in seconds.
Excel Columns We Auto-Detect
The Real Cost of "Free"
Excel is free. The mistakes it lets you make aren't.
⚠️ Formula Errors
Studies show 88% of spreadsheets contain errors. In CRE, a broken SUM or mislinked cell reference can overstate NOI by hundreds of thousands — and you won't know until it's too late.
⚠️ Hours Per Deal
Building a proper proforma model from scratch takes 4–8 hours per deal. Recovery structures, waterfalls, and tenant projections add days. Solsten generates the same output in minutes from structured inputs.
⚠️ Lost Institutional Credibility
Sending an Excel model to a lender or LP? They know the formulas might be wrong. A purpose-built platform with deterministic calculations and clean reporting signals professionalism.
Spreadsheet vs. Solsten FAQ
Common questions from Excel power users.
Why should I stop underwriting CRE deals in Excel?
Excel has no built-in audit trail, formulas break silently when rows are inserted or deleted, version control requires manual file naming, and complex structures like NNN recoveries and GP/LP waterfalls must be rebuilt from scratch every time. Purpose-built tools eliminate these risks.
Can I import my existing Excel models into Solsten?
Yes. Solsten has a guided Excel import wizard that auto-detects common column formats for rent rolls and expense budgets. Upload your .xlsx file and Solsten maps tenants, suites, lease dates, rent rates, and expense line items automatically.
Is Solsten as flexible as a spreadsheet?
Solsten handles the 95% of CRE analysis that every deal requires — proformas, recoveries, waterfalls, tenant timelines, risk scoring — without custom formulas. For truly unique one-off calculations, you can always use a spreadsheet alongside Solsten. Many users keep both: Solsten for the core model, Excel for side analysis.
Does Solsten have an AI assistant?
Yes. Saga, Solsten's AI assistant (in beta), is grounded in your actual property model data. Ask questions about your assumptions, get explanations of your outputs, and review scenarios — all without leaving the platform.
Your Next Deal Deserves Better Than a Spreadsheet
Import your existing Excel data. Get a full proforma, risk scores, tenant timeline, and Saga AI assistant — in minutes, not hours.