Hi CJ
Be carefull doing this, at least one well known provider will issue you with a final statement saying you are "eligable for assessment" in the cert iv. This certificate is not worth the paper it is written on as it does not meet national competency based training requirements and therefore cannot be used for credir by another rto. There is no such thing as getting a cert iv and then doing the apprenticeship, the cert iv requires both practical and theory.
Please take my advice: if you want to enter this industry find an employer willing to take you on as an apprentice and then go where they send you. The choice of training pathway is decided by the employer not the apprentice. If you want advice on finding an employer pm me.