Of course, this is the most expensive cleaning method (up front cost)
$200 Good rock tumbler
$40 5lbs Steel media/balls/stick OR Southern Shine Media (Stainless steel bits & pieces) for ~$27 5lbs
$20 Lemi Shine/Dawn/Shinebright
However, the steel pins and balls last pretty much forever, and the tumbler is very reliable electric motor. So you don't need to buy more corn/walnut, or whatever media all the time. So in the long run, this is probably cheaper.
But this website isn't about what is cheapest really, its about what is the best. We think this is the best.
However, for the money Southern Shine Media is the "best" value we have found and it does the job with very similar to same result as the steel pins, in perhaps slightly less tumbler time. We learned this after tumbling about 10 batches with and without it. It cleans slightly faster we think, but its hard to say precisely how much because each brass is different level of dirty somewhat.
Here is where to find Southern Shine Media:
Tell her Natoreloading sent you. We paid full price for our 5 lbs, it was not free, and Southern Shine Media does not pay us or give us anything, we have no relationship with them. Its simply the best value we found for tumbler media.