What are your favs?

So I am working on my collection.... well starting one lol I know a lot of you find some REALLY good deals on occasion at the grocery or Lowes etc....I have been looking but not really sure what is a good deal or even what would be considered rare at these places. What do you look for? what are your favs? I know a couple like the Monsteras and variegated Frydeks but I am sure there are others.