What is the law regarding a customer who refuses delivery of items they ordered?

I have a customer who ordered $12,000 worth of goods. They continually refuse delivery - I need clarification on the law. When am I able to resell the goods to another customer but still proceed with collection action on the one that ordered the good originally? There is some time limit, but I cannot recall.

you can't collect the price of the goods from the first person. You can charge a restocking fee of about 5% and thats about it. You can resell the goods the minute they refuse the goods. they don't want them, they are yours.

Is this a special order? Or is this an item or items that you regularly have in stock?