IMO, HHD is really good. Honestly, I think you should buy it!
Though, the fact that it IS a bit repetitive, could be a huge deal-breaker for you.
I bought mine used at GameStop, so I mean, to me, it was worth it....but, then again, I didnt have to pay an arm and a leg to get it.
The main objective of the whole game is to design and furnish houses by what the client wants.
So far, I've completed around 8~10 houses and a school, cafe, and hospital.
Hey, it keeps my mind busy when there is downtime in ACNL! Heh.. :3