Think of a food truck as a restaurant that lacks a permanent location and offers a tight space to work in. If you would not consider opening a restaurant, you probably should not be thinking about getting into the food truck business.

Trucks are enticing because while costs vary, it's generally much cheaper to open one than it is to launch a traditional restaurant. There's also a sort of societal romance around food trucks right now and that can lure people in who are otherwise unprepared.

Before you even consider opening a food truck business, you have to understand what that entails. Don't think about the camaraderie of the food truck festivals or the idea of being your own boss. Focus on the business above all else.

A man serves customers out of a food truck.

Running a food truck can be a challenging way to make a living. Image source: Getty Images.

Know the rules

Food trucks generally have to adhere to rules regarding restaurants and rules that relate to being a vehicle. Before you open a truck, you need to know what permits and fees apply. You also need to understand where you are allowed to park while you operate and where you can legally park when you are closed.

Have a business plan

Just because you see a food truck being sold for what appears to be a great price does not mean you have started on the road to business success. You need to have a formal business plan breaking down your costs and realistically forecasting your potential revenue.

You need to understand the cost of buying or leasing a truck and the cost of operating. That includes permits, fees, gas, parking spots, employees, and food costs. After that you need to make a reasonable guess as to what you will be able to sell on a daily, weekly, and monthly basis.

To figure out some of these things, it makes sense to talk to existing food truck operators. They may also be able to give you a sense of where the market is. Is there demand for new trucks or have they seen business slow as the market becomes glutted? Is it easy or hard to find places to operate?

Are you a chef?

You don't have to be a trained chef to open a food truck, but if you're not, it's important to understand what you are getting into. Even if you plan to open with a simple menu -- maybe you're a truck that sells meatballs and meatball subs -- you need to figure out if you can execute that menu in an efficient way.

Before you invest in a truck, run a stress test in your kitchen. Invite a bunch of friends over and operate as if you were running your truck. Can you serve the equivalent of a lunch rush?

You may have to refine your menu multiple times. That may mean doing more overnight prep work or cutting down your ingredients list. It may also mean deciding that your Peking duck and chocolate souffle food truck idea just won't work.

Be realistic

Use hard numbers and cold logic when deciding whether or not to make this leap. Don't get lured in by how cool the business seems or your friends thinking you make the "best ribs ever." A food truck is a business -- one that faces special challenges -- and it's very important to treat it as such.

Owning a food truck can be an exciting and rewarding way to make a living. It can also be a financial disaster, which explains why you see so many lightly used trucks for sale. Go into this business (or walk away from it) with your eyes wide open knowing what to expect.

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