DH questions

After trying out 2 SLs last time in Tokyo I'm planning another trip back. This time I want to try the more customizable DH and I have some questions.

1. What is the normal foreigner fee in DH? I checked price lists on Cityheaven and conveniently there's a tab for foreigners, and it sends me to another website which does have English menus and chats, but the cost is double. Is this a scam?

2. Do I absolutely need a Japanese phone number to do this? I would prefer not to call if I can make reservations online.

3. If I do have to make a call (which is fine since I found out I can make basic conversations after talking to those 2 SL girls), what kind of things should I tell the reception? Will they call back or expect me to call back?

4. Just to be sure, I need to clarify them about being a foreigner as soon as possible, correct?

Thank you in advance and wish everyone a happy time in Japan.