Spreadsheet Automation and Customer tracking

We are a vehicle hire company and use our Excel sheet for two primary functions:

Vehicle Tracker Sheet:

Tracks which customer is using which vehicle and the start date of the rental.
Tracks the rental and insurance costs for each vehicle to project monthly profits based on active rentals.
PCN (Ticket Violations) Sheet:

Tracks ticket violations by recording the date the incident happened.
Associates the ticket with the respective hirer.
Currently, both sheets are very manual and prone to data loss because:

Customer info is not stored after they are removed from an active vehicle, requiring manual re-entry if they rent again.
Rental end dates are not automatically tracked when a vehicle is marked as vacant or assigned to a new customer.
Requirements:
Customer Info Storage:

Create a sheet to store customer details such as name, address, contact number, and email, which can be referenced in the Vehicle Tracker.
Enhanced Vehicle Tracker:

Automatically update rental end dates when a vehicle is marked as vacant or a new customer is assigned.
Link customer details from the Customer Info sheet to avoid manual re-entry.
Ensure vehicle costs are tracked to facilitate monthly profit projections.
Enhanced PCN Tracker:

Automatically associate ticket violations with the correct customer based on the incident date and vehicle tracker data.
The goal is to reduce manual data entry, prevent data loss, and automate tracking and associations between sheets.