Sometimes, a Floating Market forms.
No-one knows when or where – they are emergent phenomena. Free traders accumulate oddities in their holds, the detritus of a thousand speculative trades on a thousand worlds – some trash, some too unique or exotic to sell, some which could be either. Slash-traders, smugglers, walkers of the dodgy path, have goods to unload that few legitimate markets will take. Relativists bring goods from the Outback, unheard of in charted space.
When enough fall together, a Market forms. Luggers and trade-ships, prefab modules, inflatable temps, all docked together without a plan. The long-standing Flern market drifted in the deep, tethered loosely to an infalling comet. News of the first few draws in the many in hope of a successful trade, and more come to supply the traders with necessities in turn. Opportunists arrive, hoping for their big score; agents of a hundred organizations come, seeking an advantage; the lost turn up, as they always do. The Market makes its own rules, respecting only the Sacred Deal and the Market Peace, a proplyd of free commerce out in the deep black.
Goods are offered – some comprehensible, most not. Business is done, with or without mutual understanding. Sometimes you walk away with an ancient dreaming Power, its substrate sold as a paperweight; sometimes with containers of rotted vegetation. Sometimes the rotted vegetation sells for millions of exval as an exotic spice; sometimes it calls a public health cautery squad down on your head.
Fortunes are made, and fortunes are lost, before the Market eventually disperses. The same could be said of lives.
So what are you waiting for?