Kevin, if you are doing this to make a living than you are running a business and to run a business successfully that means keeping track of what it costs you in materials and your time to make the projects and than pricing the items to make a decent return on the dollar! This also means that your customers understand that you are friendly but you require a deposit with final payment upon finish, no if, ands, or buts! If you are letting the customer pick up with out final payment you may as well forget about them ever paying for the items! In the case with this lady, for any future requests, I would double the price you have been charging and explain to her why you have to do this. Its one thing to be friends with the customers but not to the extent that they take advantage of you!
This is only my opinion and please take it for what it's worth.
Erv