We just installed our 16x12 Kozyard Alexander Gazebo May 2020.  My wife and myself installed this ourselves and were very happy with this product.  We are in our mid 50's and were a little concerned with the overall weight of the product.  The delivery was received in 4 separate boxes which spread the weight pretty evenly.  That made it much more manageable. The keys to our install were....
•	Remove all of the parts and sort.  There are multiple parts that are the same.
•	Take out all of the hardware and put them into plastic baggies and label with the part number.
•	Do not tighten the screws, bolts and nuts until you're done with a section.  This allows for all of the holes to align properly. 
This took my wife and myself about 20hrs total between 3 days.  We are extremely happy with the product.  It rained today, no leaks.