I'm so glad I purchased the trundle for overnight guests. I love everything about it. It came in three different boxes and took my husband about an hour or so to put together. There was nothing hard about it he said. I did purchase an 11' XL twin temper pedic mattress  to go on top. 11" was just perfect! not too high or low. You could go with 10"-12" for top, but anything less will show backing.  8" thick regular twin for bottom.