Looking for quiet and clean hotel near the metro in Sto. Domingo

I look for a quiet and reasonably clean hotel without any luxuries (although "quiet" may be a luxury in DR...) for a fast trip, to "verificar" my stuff in aduana in Puerto Caucedo.

I found plenty of advice, but generally the hotels are in the Colonial Zone.

By the way, how far is the colonial zone from the bus station?

Thanks in advance,