Top of my head, you are looking at:
food handling certification
permit/license/approval for your proposed pitch
guessing some form of liability insurance (garde can advise on that!)
vehicle costs/insurance
equipment costs
wholesaler account and food costs.
So this wouldn't be the cheapest business to start, and I'm not sure if you appreciate the long hours you would be working to make 1 vehicle viable, let alone further vehicle costs and staff overheads.
I'm not being a killjoy, just a realist, and as stavros says, lunch vans with a good reputation can be extremely popular, so there are potential opportunities, just be aware of the pitfalls as well
Maybe approach an established operator and see if you can get some part time work? Learn the ropes at someone elses expense, and see if flipping burgers all day is still interesting after a 14 hour day
