I wish I had added a lean-too on my existing pole barn shed. I really adds a lot of space and makes it easy to get into and out of lean-too for attachments, storage ect. We added a one to my brother's pole barn shed and it adds a lot of flexibility for big equipment that makes it difficult to store and work around in his main shed. Lean-too is a nice place to store equipment that is not used frequently but still needs to be stored out of bad weather.