Playing as Milan. In turn 4 (after having allied to some other factions) I only manage to get trade rights from the HRE.

Turns 5, the nobles ask me to send an emissary to deal with the new civilization, the HRE. At fist I was simply surprised, I sent an emissary, exchanged maps and got the 500fl.

Turns 6-13, repeat ad nauseam. The emissary is sitting beside an HRE castle and gives them the maps for free every turn (getting 500fl. from the nobles every time).