Can my friend who is moving to Thailand get a bank account sharing my apartment and with a non-O retirement visa?

If your friend has been on a retirement visa previoussly didn't he have a Thai bank account for that and has he maintained it?

Yes you can

As others have said its the law that every foreign visitor ( were all vistors regardless of visa) is registered within 24 hours (even those married with kids living in the family home). But don't get hung up on the 24 hour thing, just get it done as practically possible and enter the check in date as the date that the report is being filled in. (Dont try and back date it).

It is now a lot harder to get a bank account in Thailand with a tourist visa or visa exempt. As a result I would advise your friend to get a non immigrant O based on being over 50 in his home country before he comes to Thailand. With a non Immigrant O he will find it much easier to open a bank account.

Regardless of how this plans out he will need a TM.30 for the extension, which you will have to submit (if you have the online login details) or you'll have to ask your landlord to submit one for him.

Depending where you are you might be able to get a residence certificate with just a TM.30 without the need for a 90 day report.

Failing that I have heard of people going to immigration and asking for a letter to open a bank account for the non-o extension requirements and the immigration office has given it.

Some banks will accept just the non-o stamp some want a plethora of documents so it's going to require some foot work regardless.