But isn't there also an economy of scales argument to be made. If you own dozens of buildings and hundreds of flats, you should be able to keep your pr. flat cost lower than someone who just bought one flat.
I'm talking about things like:
* Admin costs (contracting, etc.)
* New tenant costs (marketing, agency fees, reference checks, credit checks, inventory, etc.)
* Landlords' insurance
* Extra safety checks (e.g. annual gas safety checks)
* Cost of downtime between tenants
* Cost of rectifying wear and tear (cannot recover from tenants)
There's also a difference in terms of maintenance. If I'm an owner-occupier and something breaks, I can live with it for a while, shop around, get a few quotes, and get it fixed at my leisure.
As a landlord, if something goes wrong with one of my properties I have an obligation to repair it as soon as reasonably possible.
Then every now and then you get a tenant who completely trashes a property, causing damage far in excess of any deposit, and which you're unlikely to ever recover.