You might be amazed; printing above the industry-standard 300ppi can give you a picture you can never get close enough too, but even at more reasonable viewing

You might be amazed; printing above the industry-standard 300ppi can give you a picture you can never get close enough too, but even at more reasonable viewing distances you can tell the difference in acutance. 480 ppi is a good value for the current crop of Epsons (you'd need a RIP and a lot of farting around to do better, but you can get up to 720). It's sort of like the difference between a contact print and an optical print at the same size; there's no more detail as such at a typical viewing distance, but the edges of the details you can see are sharper. As for the scanner, if you don't really need a car, you can always get a Flextight. (They really are that good, but they really are too expensive nonetheless.)