Cost-Plus vs Retail: Interior Designer Procurement Markup Calculator
Procurement is where the biggest variation in your final bill hides. When a designer buys furniture on your behalf, they pay a trade price below retail, then add an agreed margin (cost-plus). Done honestly, the trade discount can offset the markup and you still come out ahead. This calculator shows the real comparison, so you can ask the right question before you sign.
The numbers
Cost-plus means the designer buys at trade price and adds a margin on that lower number. Whether you win depends on how the trade discount compares with the markup. Ask exactly how procurement is charged before you sign, because this is the single biggest swing factor in a final London bill.
The Folio
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