Can someone please explain me about this blog I've mentioned?

[Jasraj Singh]

I was reading an interesting blog 

https://www.biggerpockets.com/...

written by Brandon Turner but I did not understand couple of things from this blog which was =

1. How is our loan for $63,500 after paying 20% of $80,000 in Year One. Shouldn't it be $64,000.

2. In year one how is our equity $46,500 in year one?

3. How is our total net worth $56,500 in year one? 

and can a property really be appreciated by 10% in one year by doing some minor repairs and improvements in it?

Can some one please explain?