What not to buy:

Succulents are highly collected in certain circles and collectors will pay hundreds of dollars for a plant. I've even seen plants that cost in the thousands, but it is hard to find these plant specimens online. This could be, because these plants are taken from the wild, and most avid plant collectors disagree with taking succulent plants from the wild. Many succulent plants, like caudiciforms, come from African countries and from Latin America. Caudiciforms take extremely desireable shapes when grown in the wild, and due to the demand for such specimen plants natives to these countries dig up the wild plants and sell them to succulent dealers in the United States. What to look for if buying a larger specimen plant: Ask the seller where they got this plant, how long they've had it, etc. Look for places on the plant's caudex that looks as though it has been cut (sometimes, when rare plants come into the shop, succulent sellers will cut off parts of the plant in hopes of growing clones). If anything seems fishy about the succulent dealer, the store, or their answers, look to buy your plants elsewhere.