Hi! I am currently using an arms reach co-sleeper with my baby but am considering purchasing a different hammock-type sleeper so he can rock while sleeping, as he really likes the movement while sleeping. The hammock sleeper would only work until he is about a year old though because of weight limits. I am trying to avoid having a crib between using the co-sleeper and getting a bed for the boy. I'm wondering what if anyone could share what they did in the transition time? and how old was your baby when you transitioned to a regular twin bed?
I can only share what we did with our toddler, and are doing with our 4.5 month old.
DS (now 28? months) - he was in the co-sleeper from birth and slowly transitioned to full time co-sleeping. He almost always started out the night in the cosleeper and came to bed at first wake up. I think we put the cosleeper up around the 7 month mark, because he seemed uncomfortable in it, and we co-slept full time until 10 months or so, when he started spending the first part of the night in the crib. Some where around a year, he started STTN in his crib. But then he regressed a bit and started coming to our bed around 3-4 a.m. Near his 2nd birthday he started being in a toddler bed (we didn't have room for a twin) and he's still there, only he started STTN again in his own bed when DD was born (he was 23 months).
DD will have a different story, partly because she and DS will be sharing a room. She has slept in bed with us full time since she was born, including in the hospital. There isn't anywhere else she'd rather be. She does spend some time in a bassinette (mostly when DH and I want the bed to ourselves) but that's it. I see eventually transitioning her to a toddler bed in our room, at least until she and DS get on a more similiar sleep/wake schedule.
We are moving soon into an apartment with more space. She and DS with still be sharing a room, but DS will be in full size bed. This way when he does wake in the night or has trouble falling asleep, one of us can easily lay with him, instead of sitting on the floor next to a toddler bed (our current back and leg breaking mode).
In your situation, I would say whenever your LO can safely come down off your bed, they could be ready for a bed of their own. You could still get bed rails if rolling off in their sleep is a concern, or place mattress on floor.
Katrina - Mama to Gabriel 11/20/2009 and Norah 10/11/2011- married to Wayne -  and now new baby Theodore born 3/11/13