About The Big Houses
Where the numbers scatter
Buying, owning, or renovating a house means chasing numbers across a dozen unrelated places. A lender quotes a rate, a county assessor publishes a mill rate you have to translate yourself, a contractor gives you a per-square-foot range that depends on finish level, and an insurance agent needs a rebuild value before they’ll even talk premiums. None of these live in the same spreadsheet, and none of them are built to answer “what will this actually cost me, this month, this year, over ten years?”
Scale that up to larger and luxury properties and the scattering gets worse. A pool, a security system, a historic restoration, or a grounds-maintenance schedule each add their own line items that a standard homeownership calculator was never built to hold. That gap is what this site is for.
What’s actually here
On the financing side, the Mortgage Calculator breaks a monthly payment into principal, interest, tax, and insurance, and the Mansion Mortgage Calculator does the same for jumbo and luxury loans that carry HOA fees. For taxes, the Property Tax Calculator and its counterpart for high-value homes, the Luxury Property Tax Calculator, turn an assessed value and a mill rate or percentage into an annual and monthly bill, with room for exemptions and a mansion surcharge.
Ownership costs get their own group: the Renovation Cost Estimator, Landscaping Cost Estimator, Pool Cost Calculator, and the Historic Mansion Restoration Estimator each work from area, quality tier, and scope of work to a per-square-foot rate and a total with a contingency buffer built in. The Estate Maintenance Scheduler and Energy Efficiency Analyzer look further out — a yearly upkeep budget, and a payback period on insulation, windows, solar, or HVAC upgrades. The Smart Home Integration Calculator and Home Security Plannerprice out connected-home hardware and a sensor layout from your home’s footprint.
For valuation and planning, the Home Value Estimator and Luxury Real Estate Valuation use a price-per-square-foot comp method adjusted for lot and condition, the Luxury Home ROI Calculator combines rental cash flow with compounding appreciation into a return and a cap rate, the Room Size Calculator turns dimensions into floor area, wall area, and volume plus a materials estimate, and the Luxury Amenities Checklist builds a categorized checklist scaled to budget and property type. Rounding it out, the Home Insurance Calculator estimates a premium from rebuild value, location risk, and deductible.
How the math is built
Every tool works from published conventions — mill-rate tax formulas, per-square-foot construction pricing, standard comp methodology, amortization math — rather than a proprietary model. We show the moving parts (rate, area, tier, deductible, and so on) instead of collapsing them into a single unexplained number, so you can see why a result changes when an input does. Where a convention varies by state or county, as property tax and insurance rules often do, we say so rather than pretending one number fits everywhere.
Beyond the calculators
The Homes & Architecture Museum is a separate, browsable collection of architectural styles, iconic houses and estates, and the design and materials behind them, drawn from Wikipedia and Wikimedia Commons. The guides and articlesgo deeper on individual topics — how a mill rate gets set, what actually drives renovation cost per square foot, or what separates a historic restoration from a standard remodel.
What this site is, and isn’t
The Big Houses is independent and supported by advertising. It isn’t affiliated with any lender, insurance carrier, county assessor’s office, contractor, or real-estate brand referenced in these tools or guides. There’s no research department or licensed appraiser behind this — it’s a working set of calculators, kept as transparent as we can make them. Every result is an estimate built from the figures you enter and general conventions, not a quote, an appraisal, or financial, legal, or real-estate advice. Before acting on a number, check it against a lender, a licensed agent or appraiser, a contractor, or your local tax authority. If a figure looks off, or there’s a calculator you keep wishing existed, let us know.