If you can come close to "breaking even" on the deal keep it. If your throwing a couple hundred away every month sale it. Don't forget that you have to pay for alot more then the just the house when you rent. Water, trash, waste. not to forget the up keep. Little things like if some 1 stays inthe house for more then 1 year you must paint the inside. Carpet cleaning between renter... it all adds up fast.
In the "long hual" relestate will always go up, the only time you really won't make money ( in the long term) is if inflation spikes very high.