Sandbags are great, you can do so much with them.
Go find some big fucking rocks and haul them off to you gym/home.
Truck tire/heavy equipment dealers will give away old used heavy tires. We just 5 of them ranging from 300lbs to 1300lbs for free. They even loaded them for us.
Use two dumbells for farmers walks. If you can use more than your heaviest dumbell use two barbells.
Work the hell out of your clean and press, regular barbell.
That's all I can think of for the moment, I know there's more.