He lives next door, but he doesn't even say hello to us.
Literal
Next [at-に] live-ているのに, he [topic-は] us [to-に] greeting even [object-を] do-not.
~のに ('even though') is the contrastive/concessive のに — distinct from the purposive のに. あいさつ ('greeting, hello') takes さえ ('even') for emphasis. さえ~ない = 'not even.' A pointed complaint.