Hey I'm just joe-shmoo, so take my two pasos with a grain of sodium (salt).
I tried using my closet, tried padding it etc. I didn't have much luck with my vocal recordings, just couldn't seem to get it right. But I did have better luck recording my guitar amp in the closest, I set my amp on a chair, sm57beat up to the grill and drapped a heavy blanket over it all.
I found my kitchen to acutally be better for vocals with out doing anything to treat it, I know, I know, how professional is that, it's not, but hey if in the end it sounds good and people like it....what can you say....DiVinci or Granda Moses it's all art, well maybe not, but if it makes a buck