Commission merchants, and agents of parties not residing in this commonwealth, be and they are hereby authorized to enter into an agreement to retain the balances of money in their hands, and pay on the same a rate of interest not exceeding seven per centum per annum, and receive a rate of interest not exceeding that amount for any advance of money made by them on goods or merchandise consigned to them for sale or disposal: Provided, That this act shall only apply to moneys received from or held on account of, and advances made upon goods consigned from importers, manufacturers and others, living and transacting business in places beyond the limits of the state.