Water bill went up super high

[Gary M caceres]

Hello! I have a fourplex. The water bill is usually 500$ every 3 months. Now there was an increase in the bill to 1,755$ for 3 months. I called the water company. They said they will send someone in 2 weeks.
I checked around the house looking for water signs of leakage. I did not find any outside or inside the house. 

Has anyone experienced something similar before?? 

Any help will be highly appreciated.