You lost any sympathy I had at it seems like landlords aren't happy enough getting tenants to bankroll their lifestyle
WTF? Landlords have to pay for a gas safety cert, elec safety cert, smoke alarms, for any new items that the property needs, for fire retardant furniture, for inspections, for a management company, and we have to pay the mortgage, insurance etc etc.
When I was last a landlord, my tenant left the flat in a disgusting state - mould everywhere, loo seat ripped off, fridge broken, cupboard doors ripped, off, absolutely filthy - the flat was RANK. And she had fucked off with her last month's rent as the 'deposit' so I couldn't even withhold her deposit to pay fot all the cleaning. Fucker.
So I don't know what you're whingeing about.
It would be ideal if everyone could abide by the rules and play fair - so if a flat has been professionally cleaned before you move in, you do the same when you move out.
Management companies should be checking for normal cleanliness, not things like taking apart extractor fans, though.