If you are using the Hosted Builder, then you need a IPhone for testing.
If you are using the Local Builder, then you need a Mac and on the mac you have the simulator, but it is recommended to test it on a real device. Because in the simulator a few functions like the camera do not work.
The cheapest would be the Hosted builder + IPhone.
And then to get the app into the store, you need a developer license that costs $99 per year.