Just a few clicks of the mouse to load code onto board. There is a wizard that walks you through everything including the initial calibrations.
As for the frame, if use wood you can make one quite cheaply and motors like the MT2213 are quite good along with 4in1 20A ESC. Otherwise something like the F450 frame is a nice option. You should be able to get it all done for around £100-120 excluding the flight controller and radio control.
The payload release should work well but if you have some spare money at the end it might be fun to investigate the electro permanent magnet idea