So we don't need to synthesize matter, altho i think it would be handy.
To start we would need some bulk mass that would need to be recycled.
And i can imagine matter re-synthesis. We could upgrade or downgrade useless but superfluous atoms and things like that.
So my idea is that mechanisms like supply and demand only work in a situation where there is less supply than demand.
High demand, High supply, price stable and high.
High demand, Low supply, price increases until demand is met.
Low demand, High supply, price decreases until surplus is exhausted.
Low demand, Low supply, price stable and low.
If everyone is a manufacturer, then obviously the demand of manufactured goods would be low, perhaps the only manufactured good that would actually see trade would be the "printer." Instead, there would be a demand for raw materials, especially the rarer elements. Division of labor would likely hold out, but for fewer things. The economy might look something like this:
Energy producers --energy--> general populace --energy--> Matter producers
Energy producers <--matter-- general populace <--matter-- Matter producers
No, because printers will be expected to be able to manufacture more printers.
Population is always increasing, people keep making more people. And they don't come out of the womb with a printer in their hands. Thus, the only manufactured good that would see trade is the printer.
But once enough printers are made (by both big manufacturers and home producers) the market will collapse.
I feel like I'm talking to a wall.