This is an extremely well built product. I was surprised and pleased that the fasteners were button-head socket cap binding posts. These take a little longer to put together but it is very sturdy and safe for the kids. The bolts also have a pre-application of threadlocker which is nice. You definitely need at least 2 adults for putting on the roof and attaching the swing-set supports. Great product, my kids love it! We added Battery-powered LED tap lights up under the green roof peak for the fall when it gets dark early.