I had a similar problem with a tenant who was amazing at first (6 figure job and super nice guy) totally wreck my place but it was a small studio but I still had to spend 15k out of pocket to make it nice again. 

Hydrojet , $300-$750 job , if it does happen more:2. add more cleanout closer to sewer line, $1k-$2k job  if you have #2 and live close by, do hydrojet yourself (or a men in your home), buy 200ft cable for only $80-$100 in amazon, that's it.once we dig deeper everything is easy. it's just napkin 

Second unit can easily be turned into a studio rental which is what we were thinking to do and rent each unit out separately.

. • Significant corporate investment in the addressable market: • Amazon’s new 3.7 million sf Distribution Centercreated 1,500 new jobs in Liverpool, and an additional hub in Dewitt created another 500• Lockheed Martin in Liverpool recently won a record setting $3 billion contract• SRC Inc. a national defense research company added 300 new jobs at its Cicero headquarters, already employing 900 highly skilled workers• Raymour & Flanigan hiring 1,000 new employees at their field support and distribution center in Liverpool• JMA Wireless investing $100 million to build out an additional 5G component factory in Syracuse to complement the existing facility in Liverpool, and bringing much of its workforce to work in the area from around the country, bringing the number of local employees up to around 1,000.• Byrne Dairy investing $28 million to expand its dairy plant in Dewitt, increasing to 300 employees at the plant• Micron Technology, the second largest semiconductor manufacturer in the US after Intel, is building a $100 Billion computer chip factor in the White Pine Commerce Park – a 1200-acre development site owned by the County in the Town of Clay.

I was also thinking of trying out Intuit's Property Management software, but then I saw the reviews on Amazon and decided to stay far away.

If possible, build a dwelling rather than just storage, even if it's just a studio. 

Last 10 yrs.33.13%11.41% Property Tax Rate$20.61$11.89 Homes Owned50.06%56.34% Housing Vacant9.02%12.45% Homes Rented40.92%31.21% AVERAGE RENT FOR HOME OR APARTMENT Studio Apartment$650$890 1 Bedroom Home or Apartment$890$990 2 Bedroom Home or Apartment$1,210$1,240 3 Bedroom Home or Apartment$1,670$1,660 4 Bedroom Home or Apartment$2,100$1,910 VACANT HOUSING Vacant For Rent3.52%2.34% Vacant Rented0.44%0.46% Vacant For Sale0.93%1.20% Vacant Sold0.25%0.46% Vacant Vacation0.60%3.97% Vacant Other3.29%4.02%

Outside Amazon, Google headquarters, Facebook etc rather get 20 offers first weekend, people viewed the empty homes and walked away.

Home Depot, hardware store, Amazon, etc.

Especially in areas where there is no shortage of land for people to print homes on, or have them delivered from the Amazon warehouse, or whatever.