I am trying not to waste money, but getting by with about 5 sippies is becoming a pain. I tend to over buy. We just retired her soft spout sippies, so I am fighting the urge to go buy a bunch of the hard spout especially because I don't know how long she will even be using a sippy.
P.S. She is in FT daycare and I like to run them through the dishwasher each time. I guess both things are factors.
Re: How many sippies do you have in rotation??
We have 11 or 12, only because I kept trying different ones to see what he liked and if I could find one that he would take milk from. Three or gour of them we never use, and I put them away.
He still takes 3 bottles a day (he still refuses to drink milk from a sippy) and the rest of the day he drinks water from a sippy. I just refill it as needed. Or if it gets floaters in it, I'll dump it and get him a new one. We use an average of 2/day. I guess when he finally weans from the bottle, we'll use more.
ETA: Oops, I totally missed the 'in rotation' part. So, I guess my answer would be 8.
We only have three plus a Foogo Thermos for longer trips out. I'm not too hyper about cleaning them (maybe should be more?). He generally uses one for milk and one for water, and I refill each as needed through the day. If the milk one gets too icky, I'll pull out our extra cup. Then I wash them all at night after he goes to bed. I put them in the dishwasher if I'm running it that night - every 2-3 days. Otherwise I wash by hand.
Three is enough for us, honestly, but I think our routine would be much different if DS was in daycare!