Okay, I'll give this a try.
"1. 1st mortgage secured by a home (occupancy doesn't matter): we can charge an origination fee and it is not rebatable."
Correct, 37-3-105 excludes a first mortgage from the definition of a consumer loan.
"2. junior mtg secured by primary residence: we can charge an origination fee and it is not rebatable (due to the recent change in 37-23-70"
"3. junior mtg secured by a home other than the primary residence: origination fee would still be rebatable."
Correct, assuming it is a "consumer" loan. It would not have to be rebated on business purpose loans.
A couple of other observations:
"Thanks for the catch - you are correct that even on first mortgage loans under $100,000 there is no ability to have a prepayment penalty. But you can have one on a first mortgage loan over $100,000."
I believe section 37-10-103 was amended a year or two ago and the $100,000 was increased to $150,000.
"I understand that SC Code 37-23-70(k)supersedes 37-3-210 - prepayment penalties for primary residences, which most of the HELOCS are secured by, and allows for capture of origination fee at application. This was a recent change."
While this may be true for first mortgage HELOCs, I'm not quite sure it would work for junior lien HELOCs because, as I understand it, section 37-3-202, realted to additonal charges, allows only for annual and over-the-limit charges, and does not allow for an origination fee, on "open-end credit pursuant to a lender credit card or similar arrangement." The definition of that term in 37-1-301(16)includs this statement, "An open-end credit agreement under which a person can effect an immediate advance by check or other draft qualifies as a lender credit card or similar arrangement." That would include our bank's HELOCs, and I suspect, a lot of others. Even though 37-23-70 would allow you not to rebate an origination fee if the fee were authorized, I'm not so sure it would autorhize the fee in the first place. This might be a good question for the Department of Consumer Affairs.