Looking for house/apartment in Dar

We are 2 volunteers looking for a furnished 2 or 3 bedroom apartment or house to rent for approx 5 months.
Some ammenities (water, elec, maybe AC, land line?)
secure, areas of Kijitonyama, Michocheni, city centre, Namaga..ada estate...??? $300usd/month

Any suggestions on how to go about looking. My experience so far with agents has not been so good.
Thanks.