Many companies have a stockpile of cell phones, handy terminals, multifunction machines, sensors and other devices that employees and clients can rent when necessary. Sometimes it gets where administrative staff feel like they work in a library, but this is a pretty important service that employees will want to utilize.
When there are relatively few devices available you can manage reservations with a calendar application, but this doesn't allow the option of managing returns.
This workflow is designed to remain at "2. Confirm Return" until it is cleared. Administrative employees, who are in charge of incoming mail, are in charge of confirming all returns.
For companies that make it a policy of renting and confirming returns with responsibility, the below one-man-workflow may do. (We must warn against the possibility of people skipping input data, such as info on the renting client.)