In 1 Samuel 8:10-17, Samuel warns Israel that if they have a king, he will take their children as his servants, he will take their best produce, "he will take the tenth of your flocks, and you shall be his slaves."
This is one of the clearest guidelines I've seen in Scripture for a government income tax rate. A king would do the outrageous thing of taxing the people as much as GOD does - a whole TENTH of your income! It's insane! We've grown far too accustomed to confiscatory tax rates above 10%, that really result in servitude. Whatever the government can't do without that much revenue, the constitution probably doesn't enumerate as its responsibility anyway.
Later, in chapter 9, Samuel gives Saul the choice piece of the sacrifice. This is not a contradiction with 8:17. We should honor the leaders that God anoints over us in ways like this. Fancy state dinners are not inappropriate, though Nehemiah was also wise not to use the huge budget he inherited (Neh 5:14-18).
In 1 Samuel 12:11 Samuel puts himself on par with Gideon and Barak! He knew his place in God's story and neither exaggerated it, nor diminished it incorrectly out of a false humility.