The $415,000 Purchase That Fails the Lender's 45% Overlay
Buyer Marcus has gross monthly income of $7,800 and monthly debts of $610 (car $410, student loan $200). He is under contract for $415,000 with 10% down. The lender quotes a 6.75% 30-year fixed loan; property taxes are $4,560 per year; homeowner's insurance is $1,680 per year; HOA dues are $60 per month; PMI is 0.55% of the loan amount annually. Automated underwriting returns Approve/Eligible at a 50% DTI, but the lender's manual overlay caps back-end DTI at 45% unless reserves are documented. Marcus has $9,000 in reserves after closing.
1. Calculate the principal-and-interest payment, total housing payment, front-end ratio, and back-end ratio.
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- Loan amount: $415,000 × 90% = $373,500
- Monthly rate: 6.75% ÷ 12 = 0.005625; n = 360
- P&I: $373,500 × [0.005625 ÷ (1 − (1.005625)^−360)] ≈ $2,422/month
- Taxes: $4,560 ÷ 12 = $380
- Insurance: $1,680 ÷ 12 = $140
- HOA: $60
- PMI: $373,500 × 0.55% ÷ 12 ≈ $171
Total housing payment ≈ $2,422 + $380 + $140 + $60 + $171 = $3,173.
Front-end ratio: $3,173 ÷ $7,800 ≈ 40.7%. Back-end ratio: ($3,173 + $610) ÷ $7,800 = $3,783 ÷ $7,800 ≈ 48.5%. The automated 50% finding is not enough for this lender's manual 45% overlay.
2. Does Marcus qualify under the 45% overlay, and what loan or debt changes would bring him under it?
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No. At 48.5% back-end, Marcus exceeds the 45% manual cap. To meet 45%:
- Maximum total debt: $7,800 × 45% = $3,510
- Maximum housing payment: $3,510 − $610 = $2,900
- Maximum P&I after taxes, insurance, HOA, and PMI: $2,900 − $751 = $2,149
- At 6.75%, that supports a loan of roughly $331,300
That implies a down payment near $83,700 on a $415,000 price, or about 20.2%, not 10%. Alternatively, paying off the $410 car would reduce total debt to $3,373 and bring the back-end ratio to about 43.3%, which clears the overlay if the lender does not otherwise object.
3. How should the agent frame the options without giving lending advice?
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The agent should present the math and direct Marcus to the lender for underwriting decisions: increase the down payment, pay down the car loan, reduce the purchase price, or seek a lender whose guidelines permit the higher DTI with documented reserves. The agent should not tell Marcus he 'qualifies' based on the automated finding, because the lender's overlay controls. The agent should also check the financing contingency deadline and, if Marcus cannot satisfy the overlay, use the contingency rather than removing it and risking the earnest money.