We just use DS's cotbed with the dropside taken off and pushed up against our bed. I made sure there was no gap between the two mattresses by shoving a rolled up blanket down the far side of his mattress. Rather handily our mattresses were at the same level, but if they hadn't have been I could have just drilled some new holes in the legs to adjust the base.
I am bedsharing with DS but DH is banished to the spare room as our bed isn't big enough for the 3 of us.
Prior to bedsharing DS was in a crib right next to me but he has outgrown it. Does anyone know of a cot that can attach to our bed so we are bedsharing in essence but he has his own space or are we off out for a new kingsize bed?!