New at IKEA is their bike trailer SLADDA. Minifablab has used it as a basis for a mobile fablab/makerspace, that can go to schools, libraries, events or wherever a pop-op fablab is needed. The FABSLADDA. Four wheels are fine on the road, but you need four legs anywhere else.
If you get an IKEA SLADDA bike trailer at your local IKEA also pick up KLAMTARE container.
Assemble the trailer except for the rear panel.
It will carry 43 kgms of makergear and should be stable when deployed in a school etc.
So I cut retractable legs from 6 mm plywood. All bolts are M5. I had wheelnuts, but wingnuts are fine too. Bolts through the top holes attach directly to the cart, fill up with rings. For the lower holes I used a tie wrap. Then there was no need to modify the cart at all and it can easily be undone.
That is it.
If you want to make a FABSLADDA, then go to the next (and last) step.