When it come to crewing and getting a film together the most expensive element of the film is usually the crew cost for labour followed by rates for different departments. Lots of people however with the price of mid tier cameras dropping all the time automatically think sound is doing the exactly the same thing. This is because they have worked with lower cameras and also where the sound was done on a zoom.
Not bashing Zoom at all for their recorders but people wanting to get in the industry started off with handheld recorders as there main mixer and recorder. This is very limiting to the mixer themselves but also damaging to the image that good sound can be captured on anything. This can be true but requires more pre production and control on the actual day of shooting.
In the video I cover this but its more about negotiation and the fact that for the price of a new C300 mk1 body its £6500 and my mixer / recorder is £5500. The lenses maybe several thousand but so is a few lectrosonics. It is important that you are educating your clients on the expense as well as the upside of these tools and worst comes to the worse sticking with your rate but letting them hire in worse gear inline with their budget.
Just remember sound is the most efficient use of money for production value on set and even in post production and stick to your rates because its easy to go down but not back up.