IMPORTANT: This post is specific to New Zealand. If you are not a New Zealand business/taxpayer then it is probably not applicable to you.
Taking the step to employ staff is a big one. But the reality is that your business can’t grow much with just one person. There are lots of details to know about when you are an employer, so getting good advice is essential (and doing what your mate does may expose you to the same legal issues he is exposed to, even if he doesn’t know it – so ask a professional, not a friend).
You need to know about your obligations relating to Employment Contracts, Health and Safety, PAYE, Holidays Act and KiwiSaver (to start with). The Ministry of Economic Development have a great website (http://www.business.govt.nz/compliance/paye-and-employment-regulations/becoming-an-employer) with lots of resources and links.