Home energy efficiency upgrades ranked by payback period: heat pump, insulation, windows, and more, with country-correct incentives applied (US IRA 30% federal tax credits, UK ECO4

Home energy efficiency upgrades ranked by payback period: heat pump, insulation, windows, and more, with country-correct incentives applied (US IRA 30% federal tax credits, UK ECO4/Boiler Upgrade Scheme, EU/DE BEG grants, Canada Greener Homes, Australia state rebates). For homeowner and energy agents. Returns cost estimates, annual energy-bill savings, and climate-zone guidance by home type, location, country, age, and square footage.

price-ascending: candidates are ordered by the listed price of the operation, with no managed-first preference applied. Unlike /v1/apis, this surface does not rank Apiosk-settled listings above federated ones — a comparison that reorders on commercial grounds is not a comparison. Pass sort=managed_first for the catalog's ordering.

Compared: listed price, settlement rail and input compatibility. Not measured yet: latency, reliability, result quality, and provider terms such as rate limits, jurisdiction and licensing.