I have never use paid themes for myself, I do what @Aree Wongwanlee does, I choose a simple theme and then customize it. It takes time but I usually enjoy the process.
What I want is to learn how to create my own themes from scratch so I can design unique themes and maybe start selling them too.
If you pay money for a theme that doesn’t mean it’s going to be unique to you.
Particularly, if you buy best-selling themes you may find many sites using the same designs as you!
another one of my themes is Metro from PixelGoose, available on Envato Market.