I too am a newbie. I received my P4 from my old dad who is 92 and never flew it. Yes pretty lucky in that sense, however................. Although never used the controller would not take a charge. A DJI authorized repair centre replaced the battery and found this was not the problem, so purchased a very good condition controller on ebay,.......$150 (yes a good price)
I then had to purchase a new tablet which was capable of processing. Purchased a brand new Nexus 7 (2013) for $180, pursuant to reading recommendations on this website actually. I received the tablet and found it to be completely incompatible with DJI GO4 App. (This in spite of following all directions to modify it in developer mode). Out of frustration I purchased an IPAD 4, $700.
After that I purchased a 128 GB Delkin 75 mbs micro usb card for $140. It stored exactly nine minutes of video then stopped working. Subsequent files were corrupted. It is currently on the way back to manufacturer for warranty replacement if they determine it to be faulty. In total that's around $1200.
To say I am frustrated is an understatement. Maybe I put out negative vibes, because every time I fly now, I expect something to go wrong.