I'd be most concerned with removing the grow equipment so I don't have to replace it later. Most of my genetics are backed up at buddies' houses.
I don't think at this point I have much that is truly irreplaceable.
But of my strains, I'm going to have to hang on to the Afghani Dream and Mass Super Skunk since they are wonderful cuts, and any of the BOG stuff because it is lovely for breeding, and of course Daddys Girl because I just can't get enough of that fruity stuff.