One of the things parents really have to decide about is the purchase of a crib. After all, the decision to co-sleep and breastfeed is attached to that decision.
We didn't buy a crib because we knew we'd always co-sleep and breastfeed. But we did end up buying a pen when our son started being mobile (at four months) so we'd have somewhere to leave him if, say, I really have to pee.
Some parents I know opted to just forego bed frames to minimize occasions where their kid might fall off the bed (or at least, if he falls, it wouldn't be from a higher point). And yes, some of them later on invested on playpens as well.
And yes, the more expensive cribs can be converted into a pen, then a toddler bed.
Anyway, aside from the breastfeeding benefits we believed in, I was honest enough to know that I wouldn't sleep well without our baby beside us. Aside from SIDS worries, it just seems to me more hassle to have to get up and lie down again and again in the times that baby is fussy.
So yes, baby stayed in bed with us. And yes, now am wondering when is the right time to introduce a toddler bed.