Leasing a car

Make sure you know of any mileage restrictions Snowbell. Some companies allow so much per year and charge per mile for anything over that allowance.

You'll need GAP insurance to fill the gap between what your normal insurance company will pay if there's an accident and what the leasing company will want. It can be quite expensive.

A private individual would not normally "lease" a car it's usually companies
Most buyers choose a PCP Personal Credit Plan it can be for New or S/H cars.
You pay a deposit, often 10% of value then a monthly payment for 2, 3 or 4 yrs, the car will have an end value set if you want to keep it you pay that, if you don't the finance company takes it back.

New cars often have a low interest rate maybe even 0% can make them a better deal than S/H, gap insurance is optional get several quotes not just the dealers price.