What is a way to get your Rabbit to Poop Less?

I have an 8 month old Holland Lop. I am planning to get him neutered in a few weeks. I love to have him out and playing around the house the problem is he poops everywhere. I know that is one way for them to mark their territory but this is seriously handfulls. I tried to Litter Train him but he did not want to be. I need help.What is a way to get your Rabbit to Poop Less?
Once he has been fixed he will get better. My 9yr old American Palomino has not been fixed and HE MARKS EVERYTHING his favorite spot is my sons bed. so he lives in the kitchen which he doesn't seem to feel the need to mark the tile. My other two I have found that adding a Litter box in the area that the seem to mark the most. But I have found that even though the two are well potty trained I always seem to find a marble or two around the house.What is a way to get your Rabbit to Poop Less?
He'll improve once he's neutered. Being an entire male it's more important for him to make sure his territory is well marked. You'll also have a lot more success litter training once you've got the 'snip' out of the way.
This is what rabbits do. I would try to litter box train him again in an area that he goes on a normal basis.