Hello there Zwer .o/ !
I have a question to ask... is the Free market possible to do for single player ? if yes what i must do to play as single player ?
Thank you very much

is the Free market possible to do for single player?

Yes

what i must do to play as single player?

Write in chat: /c game.player.force = "neutral" (it'll change your force to "neutral")
Open your inventory, find a button with prices, set sell prices for items.
Write in chat: /c game.player.force = "player" (it'll change your force to "player")

For multiplayer, it'll be:
Write in chat: /c game.players["nickname"].force = "neutral" (it'll change your force to "neutral")
Open your inventory, find a button with prices, set sell prices for items.
Write in chat: Write in chat: /c game.players["nickname"].force = "player" (it'll change your force to "player")

Prices gui: (although I changed it a bit)

Isn't that just selling to myself or something?
Is it possible to create a entity with a virtual market/auction and you sell/buy to "them" which are randomized items, and prices...
I don't mind the console commands either if necessary.
Probably its possible but its not the focus of this mod so wont happening I guess =P
Imagine selling stuff raw for cheap just to get enough to buy buildings to than make more money and buy more and repeat ?!

Isn't that just selling to myself or something?

No, there are 3 forces by default, this mod just replenishes items etc in neutral force. So, in short, your force trades with neutral force, but there's no any autoconfiguration yet.

possible to create a entity with a virtual market/auction and you sell/buy to "them" which are randomized items, and prices...

It's not included yet.

will use that commands for now ^_^
Thank you very much mate ! you and your mods are amazing!! great job!
Keep it up and Stay awesome!

I tried fumbling around with this extension adn the mother mod but I didn't get it working.
I guess it's too complicated for me 😅

Try https://mods.factorio.com/mod/trading_system instead