I just want to link to IzzyMedrano (https://www.deviantart.com/izzymedrano)'s journal cause words of wisdom like this must be shared whenever possible: http://ariokh.deviantart.com/journal/36245366/
"When you pay an artist for their work, their prices denote not just the cost of their time, the materials, or the effort for your project. What you are paying for is the cost of experience. A lifetime spent perfecting a craft, and honing an ability. You pay for all the mistakes we won't make for you, because we've made them for ourselves already. You pay for the mind that has been training to deal with specific problems, and generate kick ass ideas, and original concepts.