If the mold is caused by a leaking pipe or water getting in from outside, then you should hire a contractor to stop that intrusion immediately, then dry out the home and remediate the mold at your expense.I also recommend reading and sharing the EPA Mold Guide.

Pierce that corporate veil like a water balloon.I have a few buildings and each with 4 or less and hence residential investment loan. i agree and have come to the conclusion to increase the liability insurance by 500k. 2nd- buy an umbrella insurance from the same/different carrier. 

Because the cost of roofs, ac units, water heaters and so on don’t care if you collect $600/mo in rent or $3,000/mo.  

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.

If you don’t cook, would  you spend money learning how to boil a pot of water on a stove?

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). 

And if your answer is “give it time,” you should bear in mind that Bitcoin has been around since 2009, which makes it ancient by tech standards; Apple introduced the iPad in 2010.

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

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.