I am not saying that no one would want to buy it from you, but the fact is that you do not even know how to use this system or what it even is, so how you can plan on selling it on ebay is beyond me. What if someone is having problems with the custom system that they just purchased, how do you plan on helping them? When someone asks you detailed questions about the system before they buy it, as most people do, what are you going to tell them? Because in all actuality, you don't really have an answer because you have not even used this system to understand all of the aspects of growing in it.
IMO, you should only be trying to sell something like this if it is tried and tested. We live in a commerical society, especially in the western world, and IMO, this is the reason why, everyone is trying to make a quick buck. I have very strong feelings on this because the first time i ever tried hydroponics, was from a similar 15 site ebb & flow system that i bought on ebay. After about a week the system failed horribly, and when I emailed the seller they told me, "well I haven't actually used it, i just built it from plans on the internet", they could offer me no help, they basically ripped me off. They didn't help me. The fact is that when I did some research it took me about an hour to build something better and more suitable.
You can be angry if you want, you really can hate my guts, thats your prerogative, but I will never endorse someone getting treated the way i was, and it wasn't that they gave bad customer service, they just couldn't help me because they didn't understand what they created and were selling. That is not cool.