Change ownership of a database

Hello all:

I made a mistake. Maybe I was lazy.
I created a database and did some amount of development as postgres.

Now I need to get this changed to a log-on role say xxx-db-owner.
I have a bunch of tables , functions and user defined types.

I have created the role: xxx-db-owner.
And most important I have db backups and have a copy of the db on the
server under a different name.

And I have written the sql to to the changes for the tables, functions and
user defined types.

Question: the database and schema ownership needs to be changed also?
Is there an order I should do the changes in?
Is there a way I can shoot myself in the foot here.

Many thanks for your attention to this matter.

KBD