I do not know any realtor that would sell this property for 90k over the true value Also 12k for two furnaces is 8KISH to high.

Properties located in areas with high crime rates may be less attractive to potential renters or buyers, which can lead to lower property values and rental income.Neighborhood DemographicsThe demographics of a particular neighborhood can impact the demand for housing and rental properties.

High energy in your post, but tread carefully.

I have some investors who have bought homes to be sold in a few of my communities that I need to sell and unfortunately, that falls on me.What other structures are we seeing that allow for effective scale? 

At a very high level a property has a “tax basis”, once you exceed that basis you are subject to taxes, whether that happens when sold and paid in full or paid over timeThe loan provided by seller financing is like any type of loan where the interest is taxed at ordinary income rates.

Considering the high interest rate, the projects and COC return seems too good to be true.

They were fairly highly rated, and performed well on my extensive screening interview (we went over an hour).

Consulting a real estate attorney is highly recommended, especially for complex transactions or if the standard forms need modifications.

There are DSCR based seconds available for investment properties, however the rate and fees are high. 

I highly doubt he is building homes in Texas from his self imposed exile to Portugal to excape massive litigation that was/is coming his way.He is a marketing guy and receives a commission for referring you to the builder developer who actually owns the properties.. at least that was his SOP in the past.