You don't need to wash the outer, it's like a wrap, you just need to wash the inserts so as long as you've got more inserts than outers you can re-use.
Swamp - I did snap up quite a few BBOS, but I've sold them all on now bar a cow and a pink spots.
My stash is now 3 BBOS (I use Petit Dessous inserts), 9 Ittis (I think) with God knows how many extra inserts, and 4 WNNN for nights. I'm now getting out the wool, it's all fully lanolised so I intend to sell my Tots wrap and I'll be using purely wool for nights, can't wait.
Sunflower - I know that KirstyH on CNT is looking for some size 1 bamboo Sandy's so it might be worth pm'ing her if you ever want to get rid of yours.