What is the most expensive type of whiskey/scotch?

Any of your single malt scotchs and single barrel whiskeys are most expensive. It just depends on what you deem expensive. Some of the single malts can run over $100 a bottle the same for some single barrel whiskeys. They are well worth it. If you like scotch and don't want to pay the price for a single malt, try a blend called "Pigs Nose" it is very very good, named because the scotch is as smooth as a pigs nose. I am not kidding, it is very good. For a good inexpensive whiskey try "Makers Mark" again very good and not very expensive. Enjoy in moderation and you will learn to appreciate the finer things in life.