All popular brands like Epson, Canon, Hewlett Packard (HP) and others provide A3 printer cum scanners and all-in-one printers.
If your office is at home and everyday you need to print a large number of advertising related papers, memos and various other documents which are bigger in size than the normal A4 size paper then you should use A3 printer scanner
Actually, when you purchase an A4 size printer, then a good amount of money is wasted. And, when you look for a longer period of time, then you will see yourself spending quite a high amount of money for printing A3 size documents from outside.