I think that weight must be loaded? That is heavy.
I am trying to think back. Unloaded it was an effort for 3 to lift at all.
We had 4 decently strong guys in total move it from van to studio and it was hard work.
Something to remember is it will be a dynamic load. You are navigating stairs and corners. The balance will shift as you move and each person will need to carry an ever changing weight.
You must be able to control that as any momentum added to that shift could overwhelm an individual.
The other thing to consider is that desk edges are sharp and uncomfortable.
I am sure it will all go well. Just don't rush or do anything without thinking through thoroughly.
I would recommend a spare assist person who is spotting for corners, trip hazards etc and can jump in if the load starts to become to much for someone.