I believe that the individual scenarios the film depicted are accurate (as in they can happen), AND that the film is misleading in what it was clearly communicating, that a career as a delivery driver is full of things to trip you up, cost you money, and cause you to end up in a worse situation than you started in, as though it's basically designed to be that way.
Customers I deliver to sometimes ask me about the job because they seem to think it would do them for a little while to make some good money, and I talk to them about what it's like, generally. But I know nobody believes how much I earn a week, and I also know that the people who end up in trouble after starting are the people who haven't actually thought about what they're doing by taking a job like this. They want money now, see the job as easy, and are blind to everything else. Yes, you have to actually have a car or van. Yes, you need to pay for your insurance. Yes, you need to buy fuel. And yes, even delivery drivers pay taxes. I've seen a lot of new people start and get frustrated on the job and quit, because they have this idea that everything should be free AND they get paid the good rates AND the job will always be easy and end at 5pm.
Imagine if the self-employed job in question was gardener. Buying a spade and a hoe, being able to afford your diesel before you start getting paid, and finishing later on some days than on others are things that are just part of the job. They're actually part of most jobs, aren't they, if you swap the spade and hoe for whatever tools and clothes other jobs need you to have.