Every Car, Every Contract, Every Kilometre

Car rental looks like a logistics business and is really an accounting one. Deposits and traffic fines pass through you and never belong to you. Supplier shares differ by line type. A contract that is extended, shortened or cancelled has to unwind every invoice and journal entry it created, in order. Get any of it wrong and the profit figure is fiction.

So the system was built around a ledger, not a booking screen. A 67-account Arabic chart of accounts, every movement posting to a real general ledger, reports reading from that ledger rather than a parallel spreadsheet. Eleven billable line types — rent, extra days, extra kilometres, downtime, repairs — each posting to its own account, carrying its own supplier percentage, producing the matching purchase invoice automatically. Twenty-three cost types across separate expense accounts. Deposits and fines move as custody money, so they never inflate revenue.

On top sits the operation: a 92-field rental contract and a 24-clause printed one in legal Arabic. A calendar that refuses to double-book a vehicle. Photographic inspection at both ends of every hire. Delivery by driver or self-collection, trip fee and fuel costed separately. Fines assigned to whoever bears them — renter, supplier or office. Accident reports with repair cost, downtime and commission. Vehicle location across four states.

The closing arithmetic is where a rental business usually leaks. Extra days, hourly late penalties after a grace period you set, extra kilometres priced at return, early-return credit for unused days, deposit refunded or drawn against — all computed rather than negotiated.

None of it is safe without enforcement, so 177 validation rules sit underneath. No vehicle leaves before the deposit is collected. No charge is invoiced twice. Nothing is edited inside a closed period. No collected invoice is cancelled before its receipt. No maintenance odometer reading goes backwards. Five roles keep profit and supplier shares away from people with no business seeing them.