Changing Existing WordPress template Backend

I don’t know if this is even possible and I can’t find any threads that are really what I’m talking about.

I have bought and installed a template that I really like the look of, but the problem is it is a real estate template and I want it for selling businesses, not houses. So I made it work on the front end, but if there is any other web developer after I leave, they are going to be confused in the back end. For example: In the section where it asks for number of bathrooms, I have the telephone number. Or there is the Properties Custom Post type, but it is for Businesses.

What I want to know is: can I edit the custom post types in the back-end? Change their titles and custom fields? Is this specific to theme?

I would appreciate any help on this. I can give more specifics if someone needs them.