How the numbers are built
The operating pro forma
Altyst builds income from the top down: gross potential rent, less vacancy and credit loss, plus other income, to effective gross income. Operating expenses are subtracted to net operating income. Rent and expenses grow independently, and itemized expense lines can each trend at their own rate, so a tax line capped by law does not move with the rest.
Reserves, CapEx, and value-add
Replacement reserves, capital expenditures, tenant improvements, and leasing commissions are modeled explicitly. For value-add multifamily, a per-unit renovation budget drives a rent premium as units are turned.
Debt
Loans are sized on a loan-to-value cap, a minimum debt-service-coverage test on a stress rate, or a debt-yield floor, whichever binds. Altyst supports an interest-only period, amortization, senior and mezzanine tranches, and a bridge to refinance with cash-out. Coverage and debt yield are reported by year.
Lease rollover
For commercial deals, each tenant rolls on its own schedule with tenant improvements, leasing commissions, downtime, and a renewal probability. Base-year expense stops, percentage rent, and recoveries are handled, and free rent is booked as abatement. Mixed-use deals carry residential income alongside the commercial roll.
Exit and returns
The exit value is the forward net operating income capitalized at an exit cap rate, with income and expenses grown component-wise so the two do not drift. Returns include levered and unlevered internal rate of return, equity multiple, cash-on-cash by year and on average, yield on cost, and development profit and margin. The internal-rate-of-return solver is decimal-exact with guards against the spurious roots a spreadsheet function can return.
Partnership waterfall
Distributions can flow through a waterfall with a preferred return, general-partner and limited-partner splits, a promote, multiple internal-rate-of-return hurdles, and a general-partner catch-up.
Scenarios and sensitivities
Base, upside, and downside run side by side. Two-way sensitivity grids sweep the drivers that move the deal, and a one-click reprice solves for the bid that hits your target return.
Auditability
Every output exposes the formula behind it and the inputs it depends on. Extracted values carry their document source and a confidence signal. Self-checks reconcile the model end to end, and the same checks travel into the Excel and PDF exports. Because the engine is deterministic, a reviewer can reproduce any number exactly.
Scope
Altyst underwrites pre-tax as the headline, which is the institutional standard. An optional after-tax view is available per deal: enter your own rates and it layers straight-line depreciation (27.5 or 39 year recovery on the non-land basis), bonus depreciation (set the cost-segregation-eligible share of the basis and the bonus rate; the eligible slice is expensed in year one and its recapture at sale is treated as §1245, taxed at your ordinary rate), passive-loss carryforward, and depreciation recapture plus capital gains at sale, with a 1031 exchange option that defers the sale taxes. Because tax depends on each investor's entity and basis, the after-tax view uses the rates you provide, and every figure is shown with its formula. See the FAQ for more.