I only have experience with business leasing. However, the differences should not be great.
The most important thing is this: leasing and financing are only financial instruments, you should not let them influence your choice of car.
The most important thing when buying a car is to find out what type of vehicle best meets your needs, including the cost.
Used cars have the advantage that the initial loss has already been borne by someone else. On the other hand, with a new car you have the full manufacturer’s warranty.
Leasing is always an option if you already know exactly how long you want to use the vehicle (usually 1-4 years) and, what is even more difficult, how many kilometers you will drive during that time. All of this is the basis for calculating the contract. If you deviate from this later, it will be too expensive.
Because the leasing rates can include interest, depreciation, discounts and sometimes all kinds of services (insurance, maintenance, wear and tear), it is sometimes difficult to calculate whether the offer is cheap or expensive.
Financing is easier to calculate.
If you think that a new car is something for you, then you could also consider balloon financing. With this type of financing, you only pay the expected loss in value and the capital interest and fees. However, at the end of the term you will then have to either take out follow-up financing or pay the sum of the residual value. In this respect, it is only slightly more flexible than leasing. But it is at least possible to use the car for longer or to sell it early, although in this case you will have to pay a prepayment penalty to the bank.
If you finance a used car, you should follow another principle for your own sake. The car should never be worth less than the remaining balance of the loan. Otherwise, you will have a problem in the event of a total loss, even if the car is fully insured.
In short, whether you lease or finance, decide on the basis of what you need and can afford. The choice of financial instrument plays a subordinate role.