Alright chump, it all depends on the phone carrier that the business is using and the restriction settings they have enabled. *72-ANDWHATEVERNUMBER works on most carriers, including verizon. Most people who will let you use a phone to reach an outside line (without beige boxing) are small businesses, which makes you scum. Larger businesses, the ones who may have it coming, generally have a pbx, and from there you have an extension that you need to enter an outside line, and then call forwarding is shady from there on, depending on the carrier.
Ideally, if you targeted such a business, you'd have a grand central account forwarding to your pre-paid cell, in which you'd answer the phone as the business and abuse the caller while recording via the "4" button. Which, is certainly illegal (well, pressing 4 notifies both people that recording will be taking place), but impersonating someone's business can at least have civil charges.
And since you're an asswipe, I must say: You're responsible for your actions, I am not. I will take no responsibility for providing you with basic information, or what you decide to do with it. Noobs do stupid shit.