I would never want to be a delivery driver. Too much potential to get robbed or worse. Here is an example where the delivery man was able to fend off his assailants.
Delivery Driver Scares Off Would-Be Robbers
Situational awareness is vital to everyone's safety, but even more so if you have to go into unfamiliar territory. Practice keeping your head on a swivel in parking lots for starters. Do not have your head buried in your smart phone. It will go a long ways to make you look like a hard target and any would be attackers might pass you up because of this.