From Regulation C Commentary: [You can also find this in the GIR]
Last edited by NSFW; 05/14/15 06:55 PM. Reason: Added comment
6. Second mortgages that finance the downpayments on first mortgages. If an institution making a first mortgage loan to a home purchaser also makes a second mortgage loan to the same purchaser to finance part or all of the home purchaser's downpayment, the institution reports each loan separately as a home purchase loan.
It is better to act cautiously beforehand than to suffer afterward.
The answers I give are my opinions. Not legal advice.