It may take really long time, why are you so greedy?? You only need to spend like 10-20 cents on transaction fee if not less.
it's just an example for the question, i always add fee for miners 
i saw some big amount of tx not include fee, like my current signature payment did
If your 1btc has more than 150 confirmations, you can send it for free. Same goes to 0.5btc with 300 confirmations.
where i can get this information? it's only take 25 hours to get 150 confirmationIf you leave it to get old enough, your outputs must not be dust and your inputs must also not be dusts. The transaction size also matter other than the age.
what's parameter to described old enough?for one day? for 150 confirmations?
Quote
Transactions need to have a priority above 57,600,000 to avoid the enforced limit (as of client version 0.3.21). This threshold is written in the code as COIN * 144 / 250, suggesting that the threshold represents a one day old, 1 btc coin (144 is the expected number of blocks per day) and a transaction size of 250 bytes.
So, for example, a transaction that has 2 inputs, one of 5 btc with 10 confirmations, and one of 2 btc with 3 confirmations, and has a size of 500bytes, will have a priority of
So, for example, a transaction that has 2 inputs, one of 5 btc with 10 confirmations, and one of 2 btc with 3 confirmations, and has a size of 500bytes, will have a priority of
