The flea market is no longer miraculously unlocked upon reaching a certain level; now, you need to build and upgrade your intelligence center to unlock the flea market and gain some additional advantages.

The flea market will be unlocked after you construct the intelligence center. Upgrading to the second and third levels of the intelligence center will increase the number of offers you can place on the flea market, extend the duration of your offers, and reduce the taxes you need to pay. The quantities, durations, and taxes affected by each level of the intelligence center can be adjusted in the config file.

Please let me know your thoughts and feedback on this mod, as well as any issues you have encountered.

Known issue:

You need to restart the game to see the effects of constructing or upgrading the intelligence center. Sorry about that.