As with other low end ARM hardware the $50 I paid for the Pine64 isn’t enough for a fully working system. You will also need a serial port adapter, I recommend the CP2102 of which you’ll find millions on Amazon for under £10. Also, a micro SD card. And a USB to micro USB cable to power the board.
The total cost of this shouldn’t be more than another $40, taking the total cost of the hardware to about $90.