Using External IDs in Place of IDs
It's possible to query use an external id in place of the Fleetio id for any action where the id is required (vehicles/:id, vehicles/:id/archive, etc). To do this you should first create an external id for your account and assign ids to your vehicles. This can currently only be done through our UI.
Once your external ids have been setup you can use it to query the API. You simply replace Fleetio's id with a key/value pair for your external id. Some examples:
https://secure.fleetio.com/api/v1/vehicles/123 becomes https://secure.fleetio.com/api/v1/vehicles/accounting_id:987
https://secure.fleetio.com/api/v1/vehicles/456/restore becomes https://secure.fleetio.com/api/v1/vehicles/vin:ABCDEFGH123456789
accounting_id and vin in the above examples refer to the keys that are auto generated from your external id.