The $2,860 scuttle the analysis for me but the $1,100 is much more palatable so I'm wondering what other people's comfort zone is when analyzing a property.

Too many red flags.

While each market is different, a quality rental not in a war zone will get rented.

Bt there property is zoned R8.

Try Brad @ Red River Roofing (405) 640-8482 for your siding job. 

It will depend on your zoning, but they normally require a separate power meter for the ADU to be capable to renting long term to a traditional tenant. 

• Total universe: 348,044 real estate properties• Zoning types: 34• Zip codes: 49• 41% of total properties: Investor owned• 70% of all properties: Single-Family homes• 30% of single-family homes: Investor owned

Check the zoning to make sure this would be allowed, lots of neighborhoods are for single family homes only. 

Tiny homes do not meet code and zoning regulations in about 99% of the country.

Someone who says 'there won't be a reason to not pay rent' or words to that effect is a big red flag.