Unsecured Line of Credit for REI.

Hey guys. I just want to get your take on this. I have an unsecured line of credit with Bank of America. I pay a few points above prime. Right now I’m paying 5.25%. I plan to pay this off shortly. I would then have $30K available. I’d like to see if I can get this limit increased in order to use for SHORT TERM financing for buy, rehab & hold. Since it is tied to the prime rate ( which changes slowly), would it be a good idea to use instead of a HML. I would plan to refi into a conventional loan after the repairs. I pay a 3% fee for each transaction for the line of credit.