Budget kilometres, not naira
Most owners set a monthly fuel allowance in naira. When the price per litre rises, drivers run short and either stop working or buy fuel from their own pocket and claim it later, often with a generous receipt. Budgeting kilometres first removes that argument. Agree how far each route should be, multiply by typical litres per 100 km for that vehicle, and only then apply the price.
Know your real litres per 100 km
A van that should do 14 litres per 100 km but does 18 is either faulty or leaking fuel. You only find out if you measure distance and litres for the same period. A tracker gives distance and a fuel card or tank sensor gives litres. Without both you are guessing.
A fuel budget per kilometre survives a price change. A fuel budget per month does not.
Set a buffer, then shrink it
Start with a 10 percent buffer above the calculated litres for traffic, detours and hot weather idling. Review it monthly. Fleets that reconcile every night usually bring the buffer down to 5 percent within a quarter.
Watch idling, it is the silent cost
An engine idling for an hour burns two to three litres in a van and more in a truck. Waiting at customer gates in Kakuri or in the Kawo traffic adds up fast. Idling reports with a naira figure per vehicle change behaviour more than any memo.