Co-slept with all my boys, but the oldest was the longest at almost 4. My advice would be make sure you aren't co-sleeping on your bed; co-sleep in hers at this age, or you will never get her out of your bed. We had a double bed in the guest room, and that is where he and I slept. My husband slept in our room. I could leave my child's bed and go to ours for sleep, whatever. My son would wake up on his own, and eventually got used to it. He also was more understanding when I had to go lay down with the baby, because it was the baby's turn, etc. I eventually moved him into a single bed; then I only lay down with him to go to sleep.(till age 4-5)
I moved the other three (kids) out of the big bed when they were around 9-12months. Used a heating pad to make it warm like mommy. Took about 1 week to get them on their own at that age.
At her age, it may seem like you will never get tired of having her around, I felt that way, but at about 4, when they kick and move a lot, you do get tired. And eventually the hubby gets tired of it as well. It wreaks havoc on your sex life if the child is in your bed, too. And that will not bode well for your marriage. So I do not knock co-sleeping at all. Loved every minute of it and would do it again if I had anymore or had to do it over again. It's just like everything else in life, everything in moderation, and know when to say enough now.
Can't help you with naps, my oldest only fell asleep in his swing, and the other ones took naps on their own, or I'd let them fall asleep in their swing and then moved them.
Feel free to email me with other questions.