[cypher]

Hi & welcome to HC
You can always disinfect a second hand cage before use & then it would be perfectly safe.
I would be more worried about the damage, have you seen a photo of the cage? If a shelf or some accessories are damaged that's not a problem as you don't really need them anyway but damage to the bars could be a problem so I would either check the cage first or ask for a photo to be sure what kind of condition it's in.
The plaza does need extra shelves added to it due to the height, there's a review here that you might find useful showing how AP added shelves & set hers up.
Unfortunately there are no longer any other cages that size with a large front door available in the UK, the only other cage with a really large door is the Alaska which is still a good size but smaller than the plaza.