You are in treacherous waters here ... the prospective tenant told you they were receiving disability making them a protected class so be careful. 

Even a $50,000 home needs a new boiler, roof, water hear, and to repair regular wear and tear.

The owner has been selling the park owned homes either for cash or on a rent to own.Taxes are $45k/yearThis park is on city water but a private sewer.

The tree keeps growing and producing more fruit(money) over time and you still have the tree which is likely worth more than when you acquired it.You have to make sure it is watered and fertilized and maybe pruned occasionally.

I've put almost $25,000 into the house with a major repair for the well water system. 

(Home Depot has about 40 different kinds) You want one with a lot of silicone in it for water exposure.fwiw, what you fill the crack with doesn't really matter all that much as it's just a way to keep from needing so much caulk.

Call the local water authority.You're forgetting management (10%).

You can deduct a cruise TO an event as luxury water travel. 

I have a great agent I can recommend.Water/Sewer: $30/unit - Garbage usually goes with water/sewer. $50-60/unit is good.Garbage: $15/unit - see aboveMaintenance: 5% - coolVacancy: 5% - coolCap Ex: 7% - coolProperty management: 11% - 8% to 10% is what you'll find in the areaProperty Tax: 1.5% - nope. 2.0% to 2.2% is the number. 

Capex also has to include:roof 25 year life span, appliances and hot water heater 12 year life span, hvac 20 year life span, kitchen and bath remodel 20 year life span, etc.