[csw]

My daughter was not technically considered a toddler..but boy did she have alot of the same behaviours and in the book Toddler Adoption-The Weavers Craft..by Mary Hopkins-Best..it took about 6 months for her to feel comfortable enough, to relax..she came home a 9.5 months old..and I had been to Guat 3x and then fostered her for 1 month at the end..and even with that she didn't want to be put down to 6 months..so I just carried her alot in the sling..she had alot of sleep problems as well..but..some folks adopt toddlers and they sleep right from the start..so you never know..alot is individual temperment, how the foster family prepares them (shows them photo's of you, calls you Mama and Papa etc..) if you visit or not etc..
I personally think adopting an infant can be easier, esp if they are 6 months old or less..separation anxiety peaks for the first time at 9 months then again at 15 months old..our daughter was "peaking" right at the time I was taking her away from the foster mother..
Toddlerhood is such a cute, though demanding age..
I would say just be prepared for the worst (sleepless nights, wanting a bottle again, needing a diaper again after they were already potty trained) but most of the time I see here on the forums it works out really well..
Its important to really practice attachment parenting techniques as well...carry them as much as possible, cosleep, cobath etc..good luck with your decision..