|''begin transaction for client''| Joanna |''staff''| Bill |
|''book''|1||Truck|''on''|2004/05/08 09:01|''for''|2 days|
 * Actions
|''begin transaction for client''| Bob |''staff''| Bill |
|''book''|1||Truck|''on''|2004/05/11 07:01|''for''|1 days|
|''pay with cash $''|2000.00|
|''complete transaction''|

|''resume transaction for client''| Joanna |
|''pay with cash $''|4000.00|
|''complete transaction''|
 * Checks
|''client booking list''|Joanna|
|''rental item''|''count''|''start date''|''end date''|
|Truck|1|2004/05/08 09:01|2004/05/10 09:01|

|''client booking list''|Bob|
|''rental item''|''count''|''start date''|''end date''|
|Truck|1|2004/05/11 07:01|2004/05/12 07:01|

|''rental item subset''|
|''name''|''free count''|
|Truck|1|