I have a great tenant and very few repairs issues (I put in a new HVAC and water heater a year before I moved out) but will eventually need a new roof (house was built in 2005). 

So we raise em, train em and condition em, in a complete fantasy realm where all you have to do is want, nobody ever "fails", anything that hurts feelings is swiftly removed from existence and all of life is padded corners and warm-fuzzies..... 

Adding amenities like power, water, and a barn or pavilion could increase its value as an event space.Farm-to-Table Experiences: If agriculture is possible, create an on-site farm-to-table business where people can visit, harvest, and eat fresh produce.

Most properties are landscaped with water conservation in mind and therefore you don't have the expenses or hassle of maintaining large lawns, high water bills, large tree maintenance, etc.

While many appliances and the A/C, water heater, etc were updated they didn't update plumbing or wiring.

How long a stretch does it run to provide proper slope to drain the water effectively?

Water/sewer/trash bills are killer in the City and they are ruthless about holding housing providers responsible while letting tenants repeatedly off the hook. 

A home on water?

The water heater and furnace is downstairs, and the thermostat control is upstairs.

I think Chris makes a good point of determining the strategy - performing 1st position notes is always a safe "dipping toes in the water" type of note to go with.