@Reh N. This is so exciting!!! When I write purchase offers for investment properties I give a list of due diligence items I need. One of those items will be a copy of the water/sewer bills to verify the cost. Here is the list I used for a recent 8 unit purchase in Ithaca. This will help you verify the numbers you've been given. I usually give the seller 7 business days to provide items.
1. Any Permits and Licenses
2. Certificates of Occupancy
3. Existing Surveys or Environmental Reports
4. Gas bill for the last 2 years
5. Property tax bills for the last 2 years
6. Copy of current insurance policy and binder showing premiums and coverage’s
7. Any drawings and maps of the infrastructure and size of lot
8. Any Contracts that will be transferred to buyer at closing
9. Signed Rules and Leases for each resident
10. 2 years Tax Returns
11. 2 years Profit and Loss
12. List of Capital Expenditures for the last 3 years
13. Listing of any current problems (water, sewer, gas, electric)
14. Rent Roll with specific dwelling number, name of resident, move-in date, monthly rent, amount of deposit held, current balance, additional charges, number of occupants, and a brief history of the resident (good resident / bad resident, special circumstances, etc.)