Huge Camera Collection

Yesterday, I received a huge camera collection from a friend of my mom’s. Their grandpa passed away six years ago, and they never knew what to do with so many cameras. The cameras were stored in a damp basement, where mold started to develop. Now my problem is that I don’t really know which ones are worth cleaning and which ones aren’t. Any advice on how to approach this?🙏

Ps: there are more cameras in other boxes but these are in a worse condition. 😓