I recently did some web design samples for a client. The client was looking for an e-commerce website and wanted to see samples of what I intended to make the site look like. They were very adamant on the samples either being right the first time, or they were going to decline and move on to a different developer (should have taken this as the first bad sign, right?). I never had a client with this sort of mentality before (usually clients ask for revisions until it looks good, then move on), so we agreed that if they liked the samples, they would pay a 50% down payment and I would start development on the site (no extra cost for the samples). If they did not like the samples, they would only owe $100 for the work spent creating the samples for them. These terms were agreed upon via email as well as verbal.
Needless to say, after sending the samples they informed me that they did not like them and were going to find someone else (ouch). No problem, I sent them an invoice for the $100. I received an email the next day stating that they disliked the samples so much that they refuse to pay for them (double ouch). I politely apologized that they did not like the samples but due to the terms of our agreement, a $100 fee was owed for the work I did for them.
Today is the due date for the payment before a 5% late fee as written in our agreement. Since they don't appear to be anywhere near paying today (they aren't responding to my curtesy reminder emails either), I assume they have no intention of paying at all. I realize it's only $100, but the client was rude regarding the rejection and with the samples in hand, they could realistically bring them to another developer to use without me getting a dime.
My Question: What is a reasonable approach to getting the money the client agreed to pay me? Most options seem to cost more than the amount due.
For reference: Both parties are from Texas, USA (Dallas area); I have a written document regarding the terms of the work and design--my work did not breach the terms at all; I have email documentation regarding the $100 fee should they choose to not continue on with the project afterwards.
P.S. Hindsight is 20/20. Should have said no to the project. At the very least, should have required the $100 upfront!