Connect each booking to vehicle status, contract, and deposit

Start with vehicle and contract states and who may change them. Recording a deposit is different from placing a payment hold or issuing a refund; verify each operation separately. Make contract version retention, handover photos, access controls, and export written requirements, not assumed features.

Prepare synthetic vehicles and contracts without renter identity data. Define available, reserved, rented, and maintenance states, and allow inspection and cleaning time between contracts. Rehearse handover, return, extension, and a vehicle swap. Agree contract versions, fuel, damage, and deposit policies and charge approval before designing screens.

Rental acceptance checklist: test overlapping bookings, an extension that conflicts with maintenance, and a vehicle whose licence expires during the contract. Retain the agreed terms for each contract and link handover and return photos with defined access permissions and retention. Rehearse damage found at inspection and a charge received after return; record the decision and approver before changing the amount. Deposit authorization, release, and refund depend on the payment provider and your agreement. Test failures and repeated notifications; updating a record is not proof that money moved. Export sample contracts, vehicles, and payments and verify their relationships outside the system. These are evaluation requirements to apply to any system you choose. Have contract terms reviewed by a qualified adviser, and estimate insurance, tracking, and accounting integrations separately from the core scope.