Difference in London Terrace buildings

I think the maintenance in 405 and 410 is slightly more expensive than in 465 and 470 because they are not as far West. Something to do with the share allocations of the apartments in each building. 405 has mainly studios as does 465 whereas 410 and 470 are mainly one bedrooms. The floor also makes a a difference to the amount of maintenance. The maintenance used to be reasonable but there have been steep increases in recent years.

What happened to the windfall that they were supposed to get from upping the cost of pool access to the rentals?

I doubt it was a windfall , maybe just a trickle