The cost of the product directly reflects the amount of effort you put into the product. Or at least that is what I believe based on all those marketing classes I have taken. Pricing a product is a tricky beast.
If you have a good product, and you price it too low, the product loses its value. People will look at the product as cheap or not worth anything if priced too low.
Experiment with different prices and methods of promoting the product and the price. Have timed sales, large discounts, etc. You have to find the sweet spot. Every product has one it is just a matter of finding it. Don't assume that a $1.00 product will sell more copies than a $10.00 product, that is not always the case. In fact most times it is not.
I have developed training classes and priced them where I thought the price was perfect, $11.00, never sold a copy. The class was 11 hours in length, that is where I came up with the $11.00, good selling point I thought was $1.00 per hour of training.
Took that same class, changed the feature graphic, tweaked the description, priced it at $35.00 and sold over 100 copies the first 60 days and it is still going strong after almost a year. I am averaging about 10 to 15 sales of that class a month.
So there are many things that make up a good sale. Not just price...