If you just want to extend the OrderGroup class you can add custom properties to the class in commerce manager administration.

What are you trying to achieve.  It is hard to give answer without knowing the context

Hi Mark,

Thanks for the response.

I am trying to store email address, phone number and a password for a ananymous checkout.

If they provide a password, we will be creating the profile when the order is placed.

Currently, I created a business object with these properties and the order group id.

In the documentation, I read that meta data plus will be replaced by business foundation so that made deviate from extending Order Group or adding a new class using commerge manager.

Thoughts?

Yeah that documentation is wrong and needs to be updated.  We will not be replacing MetadataPlus with Business foundation.  We are adding abstractions to the order system and will eventually chnage the metadata plus implementation but it will not be business foundation.  When we do change it will have an upgrade path so you should use MetaDataPlus.

We havw Email and Phone already on the OrderAddress collection on OrderGroup so you could use that to store those.  You would just need to add encrytped metafield on the Cart class to store the password