Answer:
1002.14(a) requieres the notification (Form C-9) to be delivered within 3 business days. It applies to ALL loans secured by a 1st lien on any dwelling.(1-4 family). Refer to the definition of "dwelling" in §1002.14(b)(2). It is not limited to principal dwellings, so it is "Any 1-4 residential property taken as collateral in the commercial real estate transaction", as you stated.