Scaffolding

Things that can be put on scaffolding outside of the ship:

Scaffold
Base cost $60 / sq
Mass 0

If equipment on the scaffolding is disassembled, it can only be picked up by drones.

For assembling and disassembling equipment on the scaffolding, the policy Exterior Work has to be active, spacesuits with oxygen have to be available and a docking port has to be installed.

While scaffolds are billed per square at shipyards they cost $29.94 per square in creative mode and they are only billed for every 334th square effectively giving you your first 333 scaffolds for free.