We have ordered 3 of your largest cat-trees over the past several years.  We love our 4 Himalayan cats and  wanted them to have the luxury of your tallest cat-trees in order to improve their lot in life and their relationships to each other.  It has been very beneficial and a lot of fun for all of us.  When we moved from Washington to Arizona we gave one of the cat-trees to our daughter to help her improve the disposition of her feisty cat.  We couldn't be happier.  By the way, they are very easy to assemble even for a fumble-fingered guy like me!  And, the price is definitely right!