Worked it out for those who’re wondering. Assuming a drop rate of 10% for any colours, VIP 0:
Each silver bar: 470 stamina = 282 gold
Each gold bar: 1310 stamina = 786 gold
Each plat bar: 6730 stamina = 4,038 gold
Each ruby bar: 22,990 stamina = 13,794 gold
To get to Ruby 6: Total 130,044 Gold needed
This does not take into account you need gold to reset the missions with the 3/day limit. I suspect the drop rate is lower than 10%.
Can someone tell me how much $$$ do I need to pay to buy 130K gold?!