For small projects you can expect to pay between 0.5 and 1 btc, my definition of small project is one that doesn't take more than 3 or 4 days to complete and doesn't require special features.  For large projects I usually charge 1 btc / week and I will be working full-time on them.  

Those are just general guidelines and are subject to change, contact me with your project details!

- Also worth noting is that I give frequent updates (usually daily) on progress and I will make a beta version of your project available to you as soon as possible.