Before you go much further, check the legal requirements that apply to your organization. (In fact, you should keep an up-to-date list of relevant legislation and regulatory requirements so you can easily check your obligations and your opportunities such as tax breaks). Most studetns find this boring, but legislation compliance is essential to your job.
These vary a great deal according to your organization. For example, if your organization is incorporated as a non-profit body, you may not make a profit; even though you can pay people for services actually rendered and have an operating surplus. Your reporting requirements might be quite light, requiring only a fair and accurate disclosure to the board. You might not need to be audited at all, depending on your jurisdiction.
On the other hand, if you are a public company, the reporting requirements are much more onerous. You can expect to be audited by a company auditor, who will check the paper trail of a sample of invoices, authorizations, check butts and physical assets through to the final statement. If the auditor finds any glitches, he/she is entitled to check all you records and investigate with further interviews.
Legal requirements may include those relating to: