People are generally nervous about sending money over the internet to someone they don’t know, and this is perfectly understandable. While I have many clients who know that I am trustworthy, and gladly pay at the same time they send the session files, I can’t expect everyone to be comfortable doing this on the first session. So I have a very simple procedure to make sure everyone is ok with the transaction.
If you prefer, you can pay half up front, at the time the files are transferred. If you choose this method, then when I send your reference mix, it will simply have a few short dropouts throughout the song. This simply ensures that the mix is not suitable for distribution, and can’t be used for any purpose other than referencing the mix. The dropouts will be short enough that you will still get a sense of the quality of the mix, and be able to make any suggestions for adjustments to the mix.
Once you are satisfied that the mix is 100% perfect, simply make the remaining payment. I will then bounce full 24 bit mixes without the dropouts, which will be ready for mastering.