To obtain the Exclusive Taste achievement, you need to own the five most expensive cars in the game, all at the same time. Here is the list of cars you will need to collect and their retail value. An easier way of obtaining the cars without paying the retail price is by looking on the auction house. You can get cars for literally a fraction of their retail price. You may still end up paying millions of credits, but finding them on the auction house will save you millions more over the retail price.

Car	Price
1957 Ferrari 250 Testa Rosa	[8 Million Credits]
1958 Aston Martin DBR1	[6 Million Credits]
1964 Ferrari 250 GTO	[10 Million Credits]
1965 Shelby Cobra Daytona	[5 Million Credits]
1967 Ferrari 330 P4	[6 Million Credits] (Available as a Level 30 Reward)