1: concrete dumbells. The tough part is to get the bars, but you'll usually find some leftover parts you can use at a nearby construction site. Ask the friendly workers if you can have some. Cut them down to the same length.

Drill in a bunch of screws. Doesn't matter where. Make sure they don't wobble.

Get a plastic container.

Pour concrete into it and stick one of the bars into it. You can some get free concrete from the workers, as well, if you ask really nice.

Be sure to place the bars precisely in the center.

Then do the same with the other end.

There you go, your own heavy dumbells.

Not enough weight? Use some pipes

2: the lifting station. This is even easier, because you don't even have to make your own weights out of concrete. You can use old phone books, instead, for example.

Unless you want to.

But better yet, find some old tires at the junk yard.

You cant also use different ways to fill them in, if you prefer.

3: boxing bag. Tires are great for that. If you prefer something softer, you can also use sandbags.