I exploded a rectangle, then cut the corners and added some lines at these corners to make  special shaped corners for the rectangle. All single entities

I then made them polylines joined together, then I offset that. So I formed a closed "rectangle-like" figure with and offset which is a pattern to cut fabric for cushions. The size is 26" W x 22.5" D.

I now want to make several "patterns" of different sizes. I need to copy then make the rectangle bigger or smaller. And have ny dimentions adjust to the new sizes. I will be making several (10-15) per week. Then plot and use as a cutting guide.

I'm having problems "streching" it . Variying the shape also.

How can I do that? Easily?

Thank you, Gabriel