Where an operator has agreed to bill your organisation monthly, you can book with a purchase order instead of paying per trip. Make a quote first and have your finance team raise the PO against it, then book and enter the PO number at Reserve; the operator checks it and the booking is confirmed. No PO, no billing: you pay by bank transfer instead.
Those bookings are gathered into one invoice per operator each month, sent to your organisation. A hire car billed this way still has a security deposit, but it is not on the purchase order or the monthly invoice: your organisation pays it by bank transfer before the keys are handed over. The bank details and reference are on the booking page. It is paid back to your organisation after the hire, once the operator has checked the vehicle.
On a work trip, money coming back goes to your organisation, never to the person who travelled. That covers a refund and a hire car's deposit, on monthly billing or paid at checkout. The operator emails your billing contact and asks which account to send it to.
Paying now but need a PO number on the paperwork? Add it at checkout. It appears on the invoice as a reference and changes nothing else.
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