I have a Google Apps Free with 2 domain:
A company made me a very attractive confirmed offer to sell my A domain. Can i remove this domain (A) and use only B domain without losing free account? Or i need to upgrade to Business?
Please let me know - it's very important and urgent. I need take a decision!
Can i remove this domain (A) and use only B domain without losing free account
No, that's not possible. Each Google Apps for domain is a separate Google account, and unless you'd created the Google account when the free tier was running, you cannot transfer the free account status across domains