Sooner or later, they'll ask you to update or verify your personal data. All banks do it with all accounts. My husband recently received a notification asking him to verify his personal data, and he has a non-b visa (both Kasikorn and Krungthai banks). If you haven't been asked to do this yet, you'll get a lucky letter soon. Be ready.
You don't need to have a bank account to buy a condo. Transfer money directly to a real estate company or pay with cash. Many tourists buy condos during their vacation without any bank accounts. Just consult with your real estate agent
As always immigration officers like to play God and decide who is allowed to enter and who is not. Having any kind of visa is not a 100% guarantee that you will be allowed into the country