The app is basically a service for ordering/dispatching couriers/deliverypeople, so it's definitely real-time(ish) - the core functionality is for users to be able to order a delivery (with real-time cost estimate) and for human dispatchers to be able to process the deliveries through a private portal. At the bare minimum I could honestly just do it through a basic form that sends emails to a dispatcher account, so I might do that for an MVP (didn't know that term before), although that would be a very, very temporary solution. You guys have suggested a ton of useful options, so I'm going to have to spend some time just reading up and seeing what would be a good approach. Thank you for the help, everyone - it's been really useful information, and I'd appreciate it if anyone has more to add as well.
That's not really realtime. Realtime is a chat app - i.e even a delay of 10 seconds is too much. Realtime is a multiplayer game with 1000 users all at once. I'm afraid I was a little vague when I said realtime. Node.js is for concurrent realtime. Meaning it's good for a product where you have thousands of users that need to be connected all at the same time all communicating with one another.
Your app seems like a fairly standard SaaS app. The cost estimate is only "real-time" in the sense that there is some data that is crunched on the server before it's served up to the user. Users just deal with a form and they punch in their data, and then that data is shown to couriers. That's pretty standard CRUD and you don't need anything fancy. Node.js is really cool, but you're going to be a lot more productive and you're going to have a much easier time by sticking to a standard, mature web framework like Django (or Rails).
Are you fluent in Javascript, PHP, or Ruby? If not, that's even more of a reason to stick with Python and Django, because you can literally start learning Django and have your MVP up by Monday.
I am (or was, a couple of years ago) fluent in Javascript/AJAX and PHP so I could definitely hack something together with that, but Django sounds like a cool technology to learn as well.
