With regard to deposit scams, the system we have in the UK works pretty well - the landlord must put the deposit in a government-approved escrow scheme, which then decides any disputes over how much of the deposit should be held back (anecdotally quite fairly).

If the landlord fails to protect your deposit, and does so in what might be considered bad faith, a court will often order them to pay you 3x the deposit as compensation - so they all end up actually doing it.

See https://www.gov.uk/tenancy-deposit-protection/overview

It's very simple in Singapore too, arguably simpler. You go to the Small Claims Tribunal (you can get a date within days, anecdotally), the Registrar decides the claim in a few minutes, and it costs you a total of 5 quid to file the claim. The whole thing takes a couple of weeks at most [edit: or a day - see 1].

I think something similar exists in Switzerland, but the (German) landlady correctly guessed that as a non-German-speaking foreigner, I would not take the time and expense to attempt it. Imagine attempting to contest the necessity of "dusting the sides of books on bookshelves" to an arbitrator in a foreign language...

[1] "For a tourist claim, the Tribunals may fix both the consultation/mediation and the hearing within 24 hours of filing of the claim." - https://www.statecourts.gov.sg/SmallClaims/Pages/GeneralInfo...

It's even simpler in Ontario: security/cleaning deposits are not allowed.

My guess is they would be factored into the rent price.