It's actually quite troublesome to make your own equipment. If there is a hardware factory nearby, buy three long poles, five short poles and three bent poles, and then pour one 1 ton barbell (10, 25, 20, 20, 10, and fill the rest with five, leaving a few extra ones weighing 2kg. According to the length, eight people can squat and push and pull hard at the same time. Everyone has this kind of strength. Without the awesome people, 025kg is enough. ) Squat stand barbell stand bench press can be done by yourself, but you can't afford it if you have an accident. You'd better buy dumbbells. Most of them are fixed sizes, from large to small. If two people practice at the same time without conflict, those four sets are important (at least 10~20kg, the middle weight is bigger and smaller, and fewer people are used). You can pour an extra pair of 35 40 45 50 55 at the end of the regular 30.
As for rowing machines, high-pressure treadmills and spinning bikes, there are many places to buy and spend money.