Moms with babies close in age: sleeping

I’m getting conflicting advice from fellow moms and I just wonder what others personal thoughts are..I will be having our second child this fall and my son will be 21 months old at that time. When I move him to his new room should I keep him in the crib or convert his crib/get a toddler bed? I was originally thinking to switch him to a toddler bed type of thing in a couple months (when he’s 18months) but now I’m wondering if it’ll be too much. But at the same time I don’t know how much I’m going to like being huge prego and trying to bend over a crib to pick him out of it. Suggestions??