In a multiple cat household, make sure you have at least one box per cat. To be safe, I always have one box more than the number of cats. Make sure the boxes are scattered around the house, easily accessible, but not lined up. Territorial cats can own a row of litterboxes, excluding the other cats from using them. This allows the cat an escape route to the right and left from an ambushing cat.
Most cats can be very nervous in an enclosed space in new surroundings.
The lid can gradually be put on. These can aid in keeping the box cleaner. Most of all, make sure you wash the pans out at least weekly with a mild detergent. Strong fragrances can put off a cat from using the litterbox. Hopefully with these tips, you'll have perfect litterbox attendance from all your cats.