Easy Money
Place a range weapon is your secondary weapon slot (keeping your melee weapon in the first slot). Then Remove your melee weapon and drag it and drop it on the ranged weapon. This should give you another ranged weapon of the same kind, keep using it until you want to stop and sell them to shop. Better using Higher weapons (more money). Only if you can equip.
Unlimited gold
To get unlimited gold, you must have at least ten troops in you reserves. Take any unit and put them in the last spot for reserves. Click on the arrow on the right and put the unit in that location. Note: You can repeat this again, but it is not necessary to do so. Then, move the unit next to the rest of the reserves. Save the game and close your browser. Reload your saved game file and go to the barracks. Go to the end of the reserves. If done correctly, a unit will be flashing between all of the unit looks. Sell this unit back to the barracks and you will now have unlimited gold.