At my home gym we were using two milk crates resting the weights on that......someone would kick them out of the way when the set started.
pretty primative....it worked, but a bit dangerous.
We now have little car jacks (we dont have a full power rack...just a budget one with no J hooks)
they sell them at car supply, auto repair and spare parts stores(sorry im from australia....i dont know what you call them over there)
These jacks are used to hold up car trailers and can hold up to 600lbs each.
they are pretty small....adjustable and dont cost much...maybe $10 american dollars
i hope im making myself clear.
Smith machine is bad news, if they used a smith machine at a bench press contest....then train with one in the gym. but other wise stick with free weights