Here are some shots of my redneck gym. It is inside a 60' long steel barn with about a 15' height to the trusses. The barn is unheated, so most of my workouts this winter have been well below freezing. The majority of space in the barn is taken up for storage, but I have carved out a functional space for myself.
The first pic is my dip and inverted row station and my pullup bar. Both are made from basic lumber and steel pipes. I may need to narrow the dip station a little. The "resistance band" hanging from the bar is actually an old punctured bike tube.
The next pic shows my squat rack and bench, and in the foreground my no-cost homemade lat pulldown machine. I can vary the height by hooking to different loops on the rope, and change the weight by adding or removing water from the barrel. Notice the classy pink little girl bike handlebars! In the far back of the pic is my extension ladder which I run up to the barn rafters and use for weighted climbs.
The third one shows all the junk hanging from the rafters. The punching bag rope and the climbing rope behind it are both 1" safety lines left over from my days as a roofing contractor. The lat pulldown rope goes through an aluminum swivel pulley that makes it easy for me to adjust my pull angle and location. My son's car spends the winter in my way since it is useless in snow, and my old project Jeep collects dust back in the corner. Once the car is out of my way I will have a little more room for farmer's walks and shuttle runs.
The final view is just a couple of 5 gallon gas cans that I fill with a water/antifreeze mix to use as rather awkward dumbbell alternatives, and tubes of sand. One tube is half-used, while the unopened one weighs 60 pounds. The sand came in a fairly sturdy double bag setup and I have left it that way. I wouldn't try to slam it, but it works great for lifting, carrying, swinging, etc. Hefting it by the top is a good grip exercise too.
Not shown are my stationary bike and my NordicTrack ski machine. The bike is my regular mountain bike, front tire removed, set on an old stand that somebody gave to me. When the weather warms up I simply switch it back for outdoor use. The ski machine was a throwaway because the wooden slat "skis" warped to the point that they wouldn't slide in the channels. I tried some crappy old real skis and boots that were given to me and discovered that they worked perfectly. With the bike and the skier I have my stationary conditioning needs filled, all at zero cost to me!
Other than that, I have 20 wooded acres to play on. I also do plenty of snow shoveling, wood splitting, garden tilling, etc. There's no reason that all my exercise should be inside the barn!