Keep in mind that when you print on canvas you'll need an inch (or two) to wrap around the stretchers. Therefore, on a 17" printer (the 4000, 4800 or 4880) the biggest print you can make is 15" if you need only 1 inch on each side. That's really not a very big canvas print.
Unless you intend to print a lot of canvas, I'd suggest sending it out. If you're going to print a lot, then get the big Epson, the 9880. That's a BIG printer.