I've only ever had minor problems with a tipi with open door for increased ventilation and no problems with a pyramid with perimeter netting. The problems...one time left the tipi door open during the day and a group of black wasps made a nest in the peak. My son made a ball of grass that he learned on "dual survival" that we lit and used to smoke them out. Have had a couple of mice run through briefly. And the best...I awoke one AM just at first light to see a large shadow outside the tent and hear sniffing and scraping as the creature tried to get into the tent. I asked my half asleep wife if both of the dogs were over sleeping by her and she said, yes. So I drew my glock and yelled, get away. This just made the creature start digging to get under the tipi. The shadow now was a little smaller now as the foggy AM sky became lighter. I asked my wife again if the dogs were both there. Now wide awake she says, no, one dog is gone. So I said, Sit! And the shadow sat down...so the shadow was either a trained circus bear on the mountain or my dog. I then called my dog around to the tipi door. He had went out for an early AM pee break and then apparently forgot where the tipi door was. My dog just flopped down between my wife and I, having no idea that he had nearly caused us a heart attack.