Generally speaking for the US - do a video walk-through on move-in day, and the same when you move out. Do your best to document every single bit of damage that you see when you move in, no matter how small. Do your best to make sure that both are dated in a way that would be more difficult to fake. Be prepared to take your landlord to small-claims court (in most cases it’s going to be small claims); amounts over $5000 are likely to be regular court system. Check your contract carefully to see if there are provisions for cleaning on move-out, whether it’s supposed to be a deep-clean, or broom-clean. Keep any receipts from cleaning that you pay for.

Most of the time, as long as you didn’t do any damage past normal wear and tear, and you did a good job cleaning, you’re going to get your deposit back. Most of the time. Other times, you’re going to have to sue.

The only times I have had issues was when I was breaking leases, or serious damage was caused to the apartment (e.g., I had a cat that peed outside the litter box when he was mad, and they apartment needed new subflooring in a few spots).