Dogecoin fee structure?

[FFMG]

Hi,

Does anybody know where I can find an 'official' transfer fee amount for DOGE?
The other day I transfered 100000 to an address and wasn't charged anything but then I was sent D29.0 and they were charged something like D8.00 as a fee.

Does anybody know what the actual fee structure is?
Does it change?

Thanks

FFMG