Yeah, neighbours will say that but that's not what the title deeds or the tenement act 2004 says, they have the "duty to maintain" as much as I do. Just because it doesn't directly affect them, leaving the roof for 70 years and no maintenance is daft.
70 years x £2800 (current factor fees for all 6 of us per year is £196,000 🤔
If flat owners just co-operate there is no need for factors.