If you don't want to buy a crib, why not just buy a crib mattress? That's what our kids use. We had a hand-me-down crib that was great for storage, but we just took the mattress out and plunked it on the floor for them to sleep on once they started going to bed in someone else's bed. Of course, they're free range, which means they lurp on into our bed in the night, but that's fine with us. Plus, this way, maybe DH could sleep on the floor next to him and just reach out to pat him when he stirs? Maybe even a futon mattress if that's not too much of a financial burden? Good luck!