The initial rental is expressed as the number of months rentals you pay in the first month.
If the initial rental is 3 months then you will pay 3x monthly rental in the first month.
For example, if the monthly rental is £200 then you will pay 3x £200 = £600 in the first month and then £200 per month in the 2nd and subsequent months
until the end of the rental duration.
You may see this expressed as 3+35 which means 3x the monthly rental in the first month and then 35 additional payments of the monthly rental.
6+35 is 6x the monthly rental in the first month and then 35 monthly payments.
It is important to note that at the end of the contract period the car is returned and you can start a new car leasing contract with a brand new vehicle.
The more you pay in the first month, the lower the subsequent monthly rentals.