Pretty much any printer smaller than 54” will eventually make you wish you got a printer that’s bigger.
much cheaper to start off at 54” or 64” than to buy a 36” and realise everyone is ordering 4’ or 5’ wide banners and your printer is too small.
Worth noting that there is still a learning curve in owning and maintaining a printer. Then all the ink and other consumables. It might not save you as much as you think.
And as everyone else has mentioned, eventually you’ll need a laminator and cutter if you want to start bringing more in house.