Here is my whiteboard marker organizer in many colors! It has the capacity to carry 5 markers + 3 and an eraser together! Don't forget the watch the attached video for enjoying the moment where I place my markers one by one :)
Let's start the details! The overall size of the marker organizer is 25 cm wide, 17 cm tall and depth is around 16 cm including its hangers. I used a PLA material for 3D printing the entire organizer in 3 days and 20 hours and 25 minutes. Yes, it took a lot of print time. And I used CR10S as the 3D printers to fabricate my design :)
More details can be found at: https://www.instructables.com/id/Whiteboard-Marker-Organizer/
including print parameters used.