Greetings,
Leasing a car has a number of disadvantages over buying a car.
For one thing, a leased car does not belong to you. Secondly, the cost of leasing is high, considering that the car does not belong to you at the end of the lease. You can find the total cost of your prospective lease by using the car leasing calculator.
Terminating a lease ahead of schedule usually incurs penalty fees. You are usually also required to take out fully-comprehensive insurance, which is expensive. Lease payments are not tax deductible (interest on personal loan repayments is).
Financially speaking, the cheapest option is always to save and pay for your car in cash. Both loans and leases add to the cost of using a car.
More information:
Car leasing in Switzerland: 10 key tips
Car leasing calculator
Personal loan comparison