this I can tell you will crumble. I wouldn't go up in this for NOTHING!!! 20ft 4x4 that is not structural span and it's literally just stud lumber. I am thinking this is under 600 pounds of strength. I will bet anything that there is a crack someplace on those 4x4's. I would highly advise that you seek someone with construction and engineering experience to do some weight bearing calculations on this structure. I am saying these things to help you. that is it. I really feel that this is not safe.How much life insurance has your wife taken out on you? :)
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