With mine, it was done out of necessity as well at 21 months when J climbed out of her crib and we thought she had broken her arm
We put the mattresses on the floor and transitioned there so we didn't have to worry about any falling in the antics that I knew they would be up to. It was a long road for us until I tried something my Dr suggested: put them in their beds and leave the room. Wait in the hall and every time they get up, go in and quietly without making eye contact, put them back in a laying down position. I also did this when they sat up. Then I would just hang out in the hallway with my laptop or phone for a couple of weeks. The hardest thing is the chatter but at their age it may not be an issue yet. I found if I was in the room a lot with them they would engage, but better if I left the room. Some nights it did over stimulate them and D would get very angry as well as OT, but she is now the best to put herself to sleep out of my three.
I also removed the knobs from the dresser drawers as they liked to pull the drawers out at varying lengths and use them as stairs
EVERYTHING was removed from their room save blankets and beds, and I'm glad I did it.
Good luck and let us know how you get on in the process