I would just tarp it well since you have limited storage space !

I would prefer to keep it inside.

I had hoped there was a quick an easy way to fold it up. I do not see why it was designed to have those two hoppers sticking out on both sides.

I had assumed that any YM 464 was the same, but I think I even saw some that were lawn mowers. The one I originally imagined was your model appeared to have the back pick up bag that could be unbolted. A side shoot can normally be unbolted. But all of that is a royal pia. If your unit only has 2" branch chipping like the unit I found, it won't do much anyway.

http://www.mtdparts.com/equipment/mtdparts/yard-machines-chipper-shredder-24a-463b129

As you can see the one I was looking at had hoppers at both ends, with an over all length of about 7'. As for the one I was looking at, it is gone.

I would still like to know if this type of chipper shredder can be folded for storage?

Plan on disassembly the time or two you use it every year. You could probably be creative with wing nuts and lock washers when assembling the chutes. Alternately, just rent one when needed. I've started renting things that I don't use that often, saves on storage space and don't have to fight with gas, additives, running the engine dry and "hoping" the carb is actually dry, which a lot of times, it isn't.

The Model you have indicated has detachable chutes , for easy winter storage .