This occupation engaged in trade and or transport of many items. What job is it?

The job is that of merchant. You can find merchants throughout the Bible.

Source:

Ezekiel 27 Prophesy against the merchant city of Tyre

This job in bible times was normally in addition to a regular job. But unless the Lord kept the city it was in vain. What is the job?

This is the job of watchman. This job was typically in addition to other work performed. In Nehemiah all the workers carried weapons with some being specifically on watch.

Source:

Psalm 127:1

Though called by God they were mainly political and military leaders. The title exists today but the job is a lot different. What is the job?

They are the Judges. Judges in ancient Israel were rulers over the people. Today they are arbiters of the law.

Source:

Judges 2:16-19