I do go on about my cage liner's but if you cant make them then cut toppers up and put them under your fleece they are washable and never smell as it soaks up the pee and because the microfibre is airy the pee dries and it stops it smelling and keeps the fleece dry.
I used to use puppy pads when i had my boys in the nero 4 cage and they worked well for me. I still buy them now for floortime and i get mine from B&M Bargains Â£4.99 for a pack of 30. I cut mine in two to fit under the willow tunnel as they like to wee under there.
Now in the cage a use washable absorbent bed pads these ones:
I have 4 altogether 2 to go in my 2x4 c&c cage and two spare, they work great with fleece on the top.