The trading post in Banished is of great use when we are lacking foods, logs, stones. When you want to acquire new seeds of plants, fruit trees, livestock.
When it’s cold and we need some warm clothes, firewoods. When the stock of tools was totally exhausted.
When you have reached an advanced level, and you want more luxury products.
In times of crisis, it will be better to have at least 3 workers in the job.
In Colonial Charter, we can build posts dedicated to certain materials so that we depend less on luck. Domestic animals can only be obtained through the trading post, or with a craft that will go in search of animals through the map, which will take more time in the end.
To optimally manage this building, it is necessary to check the inventory in the Town Hall, to see what we have in excess. It will be better if it is materials rather than foods that can quickly run out.