Minimum tx amount where amount = fee What is the absolute minimum amount which when transferred over a tx its value equals the tx's suggested fee? Is it the dust amount of 0.00005430 BTC? How is this value affected when that amount is the only unspent output spent in the tx and when there are more unspent outputs than just this one?

Relevant question:
What&#39;s the minimum transaction with bitcoin?
There is no minimum amount. You can send 0.00000001 btc and even 0.0 btc without fees and there is a possibility that this transaction would be mined by some miner. But the probability is very low, because "standard nodes" (by bitcoin devs) do not relay such transactions.

You should add a fee if you want to send less than 0.00005xxx (I do not remember the exact value). The fee is 0.0001 per kb for clients running 0.8.x and 0.00001 per kb for clients on version 0.9.x

Here you can see transaction which transfers small amount of btc with a higher fee. https://blockchain.info/ru/tx/b07f23ce5d6a3746a3f8bd5202daa1084686812aa4ecce290208fbe84e68f564