Hi Corhen,
I was a nanny of twins & I'm hoping to adopt twins or have 2 that are close to the same age
I had 2 of the bouncy seats, it made feeding times much easier when they started eating baby food. I could put them both in there, sit them infront of me and alternate mouths
When they got older(and too big for the sink) I had 2 seats that went into the bathtub so I could bath them together. One could sit and play in the water while I washed the other and vis versa.
I did have 2 slings. I carried the boys a lot of the time when they were little. But I made them myself
lol
The only other thing I had 2 of(and ONLY because the parents were rich and could afford it) was the really nice exer-saucers. I think the ones we had were in the $120 range...I dont' think you really NEED them..but they are nice if you are going to be the only caregiver and NOT have a full time maid
lol I could put the boys in them and get the kitchen mopped or the laundry folded etc.
I would not buy anything major like exer-saucers until the kids arrive
Some children just HATE them.
I'm sure there will be other people chiming in here soon