Hey Betty Boop
I don't live in Tga, but have lived in the Mt (across the bridge). If you're looking at coming this way then I could probably give you some tips, but Tga I'm not too sure of really with regards to community centres or healthcare centres.
Suburbs: most are nice so is probably easier to say one to avoid that is a rough area would be Gate Pa. Welcome Bay is a nice probably affordable suburb. Schools/Daycares: well depends which suburb of course you end up in, as there are quite a few, & I'm guessing you're thinking of Primary being that you're oldest is only 4. I know the Secondary Schools in Tga are really good.
Sorry not that much help, but if you end up in the Mt I could probably give you some more pointers

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