Apps how much for implementing google licensing in our game?

[xAVENUE]

Hi Devs,

We are a group of amateur developers from The Netherlands and would like to know how much would it be to implement google play licensing in our app:

https://play.google.com/store/apps/details?id=r.b.r.free&hl=en

also how much would it be to implement microtransactions/in app purchases? Simple purchase of the coins?

Please, let us know here:

piotrkwiakowski@yahoo.com

Greets from the Amsterdam,

Piotr