If they are VERY professional, they will have their processes in writing as verification that policies are enforced equally and fairly by their entire staff.6.

I wish I had such clarity on my path in life at such a young age.

Other reasons for denial involve other risk factors, such as, 1. rental history and prior landlord verification 2. credit score3. employment history and verification4. income v. rent ratioetc. 

The owner was renting the property and was getting close to retirement age.

The form states: "All claimed transactions are subject to verification.

Owner financing is like a secret weapon for folks looking to sell their properties after hanging onto them for ages.

Age, Race, Familial Status, etc, are irrelevant.

In this day n age a buyer either has there pre-qual letter, a verification of funds, or nothing.

Some go by the SQ FT to estimate but the age of mechanicals can swing the budget

Your handiness and experience will get you a long way as it already has, being a partner in 2 deals at this age.