How much does it cost?

To start with, there's no need to spend a lot of money.
Forget expensive and fully automated drones like Parrot or DJI.
I do not say that these devices are bad, I say that to begin, it is better to use a drone inexpensive.

So how much does it cost a cheap device? You can start with the sum of ... 15$. And at that price, if you choose well, you have a fully operational machine, which flies well, with which you will be able to learn the rudiments of piloting, to acquire the automatisms. And if you don't like it, or if you break / lose your drone, you will not have to cry the 500 Euros of a Parrot or other ..

These cheap little toys will give you a real pleasure, a real sensation of piloting.
If you want to go further, you can type in 30 -40$, with drones a bit bigger, often equipped with cameras to make small shots or drones more comfortable in external piloting.

What drone to start?