USDA guaranteed is moderate income or lower so it depends on cost of living in your area and for that
State for example in Alaska a single person could earn up to 157,000 depending on the county. Alabama and the first first A states are just under 75,000 for a single person. That said it was very definite that all persons in the household who have income count and there are other projections for income as well.
It is not a easy loan to qualify for and it has many stipulations whether it is a direct or guaranteed loan.
You can see if your lender is registered with the
USDA on the USDA website as well.