M4A1S Hyper Beast Minimal Wear is a Covert rifle skin that was introduced to CS:GO as a part of the Chromatic Scale on April 15th, 2015. The skin is a part of the Chroma 2 Collection and is one of the random rewards that can be obtained by opening the Chroma 2 Case.
In terms of design, the M4A1S Hyper Beast features a custom psychedelic paint job with an image of a vicious creature on the side. The M4A1S Hyper Beast comes available in all five different exteriors. It also has the ability to be equipped with StatTrak kill count technology.
In terms of prices, they can widely differ depending on the StatTrak technology as well as the quality of the skin exterior. On the lower end, the Battle-Scarred version of the skin will only set you back a few dollars, while the higher tier exteriors such as the Minimal Wear can usually go for upwards of $30.
You don't need more sell skins for real money; on DMarket you can trade CSGO skins for other skins.