Why pay for a consultation when I can get one for free?

You can get some excellent advice free of charge, but it is worth remembering that usually free advice is only free at the point of use, you WILL still be paying in the end with the assumption being you will buy through them. The designer in this circumstance is usually be working to commission, meaning there can also be a conflict between giving you the best design, and earning as much commission as they can (bare in mind, they are often on minimum wage + commission)

If you pay for a consultation you can be certain the designer is working for you and only you, able to recommend parts from any supplier which best suits you and your budget.