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# Overview

Direct expense endpoints mounted at `/expenses`.

## Quantities and units

Expense line items follow the same `quantity` and `unit` rules as bill line items: `quantity` accepts fractional values to 4 decimal places, and `unit` is an optional label of at most 50 characters. A line tied to an inventory item through `sku` takes the item's selling unit unless a different `unit` is sent, and needs a whole-number `quantity` when that unit is `EACH`.

Line items in expense responses return `quantity` as a number, `unit` when the line has one, and the `sku` of the inventory item the line is tied to.

Money values come back as decimal strings: `rate`, `amount` and `vat` on line items, and `value` and `amount` on adjustments. Requests send them as numbers.