The theory sounds good, but in practice we can see that rents stay quite stable as a ratio of income, and not as a ratio of interest rates, or house prices, or anything else that would be a landlord cost. Check out the rent to income ratio in your own municipality and compare to, say, rent-to-interest rate, or rent-to-property-price. Landlord costs only get passed down when there is significant room to increase rents in the tenants income and there is insufficient supply to handle the number of potential tenants.