I'm moving my home theater into the basement of a condo. Above is the rest of my condo (and above that and to the sides the neighbors), but I still want to make sure that the neighbors won't be complaining when I'm watching movies or listening to music. First off, it has a hanging grid for the ceiling with 2'x4' ceiling tiles. I'm going to replace all of them since they are old, dirty and sagging. I think I will be replacing them with Whiteline ceiling tiles. I need about 60 total. So, it'll cost under $500 for those. Not too shabby. That'll take care of reverberations and will finish off the ceiling nicely, but it doesn't take care of the sound transmission to the neighbors. I don't think I'd do much with the walls, since they are not common with any of the neighbors. Plus, replacing drywall would be more work than I'd like to do. However, I do want to get some sort of barrier sheet/material to line the ceiling before I put those tiles up. Any CHEAP suggestions that will do a decent job of containing sound? Thanks!