Materials Estimator with Waste Factor

The annoying part of any build isn't the building, it's working out how much of everything to buy, then realising you're three screws short on a Sunday. Give it the project and dimensions and it returns a proper materials table: quantities, a sensible waste percentage per material, the consumables you'd forget, and a rough cost in your currency.

I am building {PROJECT_DESCRIPTION}. The key dimensions are {DIMENSIONS}. Generate a complete materials list that includes: the primary material quantities needed, a recommended waste factor percentage for each material type (and why), any consumables I might forget (screws, sandpaper, adhesive, filler, etc.), and a rough cost estimate in {CURRENCY}. Present this as a table with columns: Material, Quantity Needed, Waste Factor %, Total to Buy, Estimated Unit Cost, Estimated Total Cost. Add a short note below the table on where to source unusual items.