What nobody tells you about maintenance costs in Bengaluru

Since the kids moved out last year, I've been checking out flats near Sarjapur Road. We're downsizing, want something manageable. Prestige City and Keya Life By The Lake look promising. But I'm worried about maintenance charges after possession. Are they reasonable, or do they shoot up? Also, for older projects, did the RWA take control from the builder, or is it still a fight? Any experiences with these builders in Bengaluru?