Just finishing up a round of fresh condos. This is a simple but effective design I use, but with a slight twist. I converted a slightly larger bucket into a concrete "form" that I can use over and over. I hate wasting 5gal buckets, and I like the slightly wider base these have. The pipe has a nail driven thru the bottom to help strengthen the concrete and keep them in place. I just use some pieces of duck tape, which can be reused several times, to hold the bucket together while the form sets. One screw at the top and another halfway down holds the pipe in place till it sets, then I remove and reuse them. Takes 2/3 of a bag of sackcrete, so I get 4 out of every 3 bags. I usually add halves of nursery pots to the top of every other pipe for more shade also. I just do one every 24hrs for a week or two, then make a covert trip to drop em. Got about a dozen ready to roll!