Hi jamest, welcome aboard!
Have a look at the 'stretch' command, it will allow you to select parts of your geometry and stretch/move them all at once. Having 'ortho' or 'polar' set is also very helpful (look them up too).
If you want something a bit more technical look into constraints in BrcsCAD, to get the most out of them you may need at least the Pro version.
hope that help, cheers.