Retainer options are not often used by small businesses and often don't make sense in general for this market segment.
Startups have to be run as lean as possible . In South Africa , they are run so lean that they don't have a budget for legal services. The course of action followed is usually :
1. Follow the law and requirements as best you can with Google search and act in a Bona Fida way
2. If you have a major legal problem , close the business and hide behind the liability protections it offers.
Established businesses are of course different , and maybe the only money you can extract out of companies in a value adding way is when they reach R2-3m turnover.