When considering purchasing die cast cars you need to know what size of the car you want.  Normally, sellers list these vehicles by Scale. Scales are applied just like you did with ratios back in grade school.
1:1 scale means that the item is actual size
1:2 scale means the item is half the normal size.
Generally, you will see collectible cars advertised in three major scales.  1:24, 1:18 and 1:24.
A 1:18 Scale vehicle (Crown Victoria Sedan) actually will measure in the area of 11.5 inches.  Depending on the manufacturer of the die cast model.
A 1:24 Scale vehicle (Crown Victoria Sedan) actually will measure in the area of 8.5 inches, and again this may vary a slight amount depending on the make of the vehicle.
A 1:43 Scale vehicle, and the most popular size, will measure about 5 inches long.
Remember those match box cars you had when you were a kid?  Those are normally a 1:64 scale and are about 3 inches long.
I have been 'playing with cars' for years and I have found that most of the questions I field at Ebay are regarding the size of the car.
Hopefully this information will help you with seeking and purchasing die cast collectibles here on Ebay.

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