Google Play Store – How to Find Your Google+ Reviews and Ratings

This was before, but now all Google Play developers can reply to user reviews. check this article: All Google Play Developers Can Now Reply to User Reviews

In order to reply on reviews, please follow these steps posted Here in Developer console help center:

1. Sign in to your Google Play Developer Console.
2. Select an app.
3. On the left menu, click Ratings & Reviews > Reviews.
4. In the "Reply to this review" box, type your response.
5. Select Publish Reply.

Screenshot for clarification:

According to the Google payments help page Change your home, business, or billing address and country:

Each payments profile can be associated only with one country due to tax regulations on the payment methods you pay with. You can't change the country for an existing payments profile and need to create a new profile to add another country. Creating a new payments profile in another country does not affect your existing services and subscriptions. They will continue to be paid with the associated payments profile.

If you are moving or traveling to a new country and want to sign up for new services or pay for products in that country, you will have to create a new payments profile.

When you have multiple payments profiles set up with different countries, you have the option to choose the account for payment.

Create a payments profile with a new country

1. Sign in to Settings.
2. Under Payments profile, click the pencil icon next to Country.
3. Click the link to Create new profile from the message that appears.
4. Click Continue from the next message that appears.
5. From the drop-down list, choose the country to associate with the payments profile you're creating.
6. Enter the address information and click Submit.