There would only be 1 toilet for the entire property.

proactively we brought water over for drinking and buckets of water for toilets. 

In regards to water mitigation, you can install water efficient toilets and water efficient shower heads.

Obviously willful damage - like concrete in toilets, cabinets torn off the walls, etc - I would definitely file a police report.

Hey fellow landlords,I've got an older property that the tenant has complained about a toilet backing up and smell coming from the toilet/and or pipes.

I would suggest winterizing, drain the water lines, antifreeze in toilets, leave lowest faucet open etc, incase the heat shuts off 

A faucet is or toilet is used 10X as much, more spills on carpet and more damage to walls, etc. 

However before I signed the offer I was actually able to go look at the property and found it has a couple issues like bed bugs in the upper unit, a sinking toilet, old furnace and some leaking sewage in the basement as well as all the windows needing to be updated and a couple new doors.

I prefer to be the bank and buy RE notes where I have all the leverage and none of the headaches dealing with tenants, toilets, or trash.

The roof sounds like it needs to be done sooner rather than later, but how many of the other repairs are things that need to be done now vs can be done down the road (eg leaky toilet vs small hole in the back of a door)?