Pure-function engines · change anything, everything recomputes · rates & tax tables externally audited August 2026 · verify before relying on them
Stamp duty models standard, additional-property and first-time-buyer rates for all three nations (£40k surcharge de minimis applied; the cockpit assumes an investor purchase); the 2% non-resident surcharge is not modelled.
Decision-support software, not financial, investment or tax advice — outputs reflect the inputs you set; always do your own due diligence.
Sold prices & ownership: information produced by HM Land Registry. Crown copyright and database rights 2026.