If you click on File->Page Setup, you should be able to adjust the paper size, scale, whether to print 3d/furniture list etc. But you are limited to the size of your printer.

The PDF printers, otoh, will allow you to choose paper size. In "Page Properties", click on Page format->Printer, select PDFCreator (as and example)... You can then change size, dpi etc, as you wish (if you go deeper ).

Good luck.