Permaculture market gardening - post harvest station

Hi all,

inspired by a video from curtis stone i am really wanting to start market gardening.
 

Now i really want to go start the beds, however it is recommended to first build the post harvest station.

While it seems i could replicate what is shown in the video,
i have another specific requirement:
I want do build my post harvest station into a vehicle,
so that i can use it on different locations, as my current
plot is too small( ok, not too small per se, but i planted it with trees).

So i am looking for some smart ideas as inspiration.

Oddly the search here did not give me anything,
so do you have something to share?

Any input is appreciated.