I had to move the extra heavy box upstairs to main landing to be able spread out for assembly.  Suggest getting 10" or 12" so guests do not "feel the slats on their backs when sleeping flat." Unsure of how I like the slats not being screwed into place, they supplied velcro for side rails, worried if mattress will fall. Updated 12/27/2019: photos with headboard - Bed ensemble. Note: bed has some slight noise to it when sitting, laying or turning. Mattress did not fall! Good to know it's only used as a guest bedroom now that the adults left after the holidays.