Flat fee and percentage
Flat fee
Section titled “Flat fee”A fixed amount added when the option is answered. It is available on every option type and is the right default whenever the cost of an add-on does not depend on the product.
For choice options, the fee is set per choice, so one option can price each entry differently:
| Choice | Price |
|---|---|
| Standard box | — |
| Gift box | +£4.00 |
| Presentation case | +£12.00 |
For a checkbox, text field or date, the flat fee is a single amount charged when the option is answered at all. File-upload pricing will be supported when that option is released.
Percentage of product price
Section titled “Percentage of product price”Adds a share of the product’s own price, rather than a fixed amount. Available on choice options.
Use it where the cost of an add-on scales with the item: insurance, gift wrapping proportional to value, or a premium finish that costs more on an expensive piece.
| Product price | 10% option | Added |
|---|---|---|
| £20.00 | Express handling | £2.00 |
| £150.00 | Express handling | £15.00 |
The percentage is taken from the product’s price, not from the running total, so two percentage options do not compound with each other.
Choosing between them
Section titled “Choosing between them”Ask whether the add-on costs you more on a more expensive product.
- Gift wrap costs the same roll of paper whatever is inside — flat fee.
- Insurance against loss scales with what is being insured — percentage.
A percentage on a cheap product can round to a trivially small amount. If there is a floor below which the add-on is not worth offering, use a flat fee instead.