In AutoCAD, what is the best way to set up repetitive architectural building plans in terms of using single or multiple drawing files and block?

copy save as (enter new name and save) ...... if there are minor changes to be done

blocks for sections ... always make sure your scale factor is correct

Well, I think the best method is to use Blocks and Xrefs. because they are much easier to share and transfer between users and designers

agree with previous answers