AirBnB trying to charge me for damage

All I have to add was I had a crappy apartment in Trastevere with shady management also.

Your approach will get you banned from Airbnb, is that what you want?

As a former property manager, here’s my take—You don’t say if you signed any papers or if it was you who phoned the locksmith. If the answer is no to both— you’re good to go. Generally, it’s the property owner who is responsible for the expense of repairing a defective doorlock. In any country, one can expect that a door with no door handle that requires a guest to open the door by using the lock mechanism—- that lock mechanism is going to be prematurely damaged. In this case, ( I don’t know Italian law, but this is just common sense) it is not the responsibility of the guest because it becomes “normal wear and tear” on a door that has no door handle. I would take it up with Air B&B and let them know if they plan to hold you responsible. you will tell your story to every online travel site you know of ( RickSteves, TripAdvisor etc.)
If Air B&B then insists on charging you $629, you should dispute the charge with your bank that issued the credit card. If this is actually fraud on the part of the apartment owner or those whom the apartment owner contracts with— don’t be afraid to use that word with your bank in the written credit card dispute. Pressuring a traveler to agree to repair charges to open the door to a property they are already contractually obligated to pay for—— smacks of coercion. And that voids anything you might have agreed to or signed when you could not get into the property you rented.
Making you responsible for a doorlock on a door with no handle seems ridiculous on its face. If Air B&B doesn’t back its customers and that means you have to part company with Air B&B— what have you actually lost? Apartments can also be rented through Booking.com and VRBO.
Finally, in 2025 it was required under Italian law that all property owners or managers personally meet with the guest at the time they are first checking in. Did this happen in your case? If not, the owner broke the law.
Good luck, and let us know how things turn out.

I just skimmed because the post is long, but as a European resident, yep keys are gold and expensive. 500 to open a locked door is normal plus 150 for the key. They offered to pay half. Not many places would. Just pay and be done with it. You are thinking like a North America who goes to the local hardware store to have keys made for five dollars. Here we have to have papers to show we have the right to ask for a new key and then it’s 150 and up. The older and more unusual, the more expensive.
Think like a European. Pay your half, move on, enjoy your trip memories. Unlike what the previous poster wrote, his US rules are not universal. Common sense in one country isn’t necessarily common sense in another.
Maybe we could put all the locksmith interventions under scams. LOL

An emergency locksmith does cost an absolute fortune but I’d still dispute the charge with Airbnb. Operators have mandatory insurance through Airbnb but as I understand it they have to attempt to claim damages from guests before they can claim on the insurance.

So I’d reply saying you don’t intend to pay and suggest they take it up with their insurance.

"You had to turn the key around multiple times."

This is standard for locks in many countries, including my own. The fee seems about right for an urgent job. You should have just accepted their offer to pay half. Just because something is expensive doesn't mean it's a scam.

I'm an Australian, and the last time I got a locksmith was years ago in Australia, and it was $500 to open a door. It took him five minutes.