If the firearm is still licenced under the old act ie it is a green licence no competency is required.

If the firearm is licenced in terms of the FCA a competency certificate is required, normally SAPS makes a business licence holder sign an undertaking ito the act stating they will only issue firearms to a competent person. Nothing can be found in the Act that specifically covers this for business firearms other than security service providers.  Bearing in mind  the general requirements for competency it makes sense  to only let a competent person use a business firearm. One should always act cautiously and conservatively when allowing a third party to use a firearm.