Loading low-level design…
Loading LLD design...
Design an object-oriented car rental system that manages a fleet of vehicles across multiple branches. Customers can search for vehicles, make reservations (including one-way rentals), pick up and return cars, with pricing determined by a pluggable strategy.
The system models a vehicle hierarchy (Sedan, SUV, Luxury), reservation lifecycle (pending → confirmed → active → completed), branch-based fleet management, and swappable pricing strategies (default, weekend surcharge, loyalty discount).
Browse available vehicles
Search for vehicles by type, branch, and availability dates
Make a reservation
Reserve a specific vehicle for a date range with pickup and drop-off branches
Cancel a reservation
Cancel a pending or confirmed reservation and release the vehicle
Pick up vehicle
Mark the reservation as active when the customer collects the car
Return vehicle
Complete the rental, calculate the final cost (including late fees), and update vehicle status
One-way rental
Pick up at one branch and drop off at a different branch
Dynamic pricing
Apply different pricing strategies (default, weekend surcharge, loyalty discount)
Manage fleet
Add/remove vehicles and branches; mark vehicles for maintenance
Before diving into code, clarify the use cases and edge cases. Understanding the problem deeply leads to better class design.
Identify the primary actions users will perform. For a parking lot: park vehicle, exit vehicle, check availability. Each becomes a method.
Who interacts with the system? Customers, admins, automated systems? Each actor type may need different interfaces.
What are the limits? Max vehicles, supported vehicle types, payment methods. Constraints drive your data structures.
What happens on overflow? Concurrent access? Payment failures? Thinking about edge cases reveals hidden complexity.
The complete explanation is included with Career and All Access. Compare it with your approach once you’ve worked through the problem.