Thanks To Swartenhengst, who copied the data, here's a list of the maximum number of busienss you can build per town. If you exceed the critical maximum, a bug in the program will make all inventory and the pruduction unavailable. Once you demolish the businesses that exceeded the citical maximum, you accumulate again goods in your warehouse, but the prior inventory is gone!
hunting lodges 401
cattle ranches 262
grain farms 410 (who will ever exceed that number?)
hemp farms 211 (cricial maximum)
saw mills 158 (critical maximum)
pitch maker 36
vinyards 237 (critical maximum)
sheep farms 231
Edit: Thanks to Ugh!'s comment I changed the language to critical maximum for the known maxima. Please post here if you know of any other maxima. If you are moderator, please edit this post and add a notation (critical maximum) to it after changing the number.
edit 2: after playing on a very difficult map, Fruehe Gruenderzeit by Frank I found new save maxima. I will update them as the game goes on
brick yards: 220
pitch maker: 80
these maxima have only been tested in P III V 1.1