RTCxTSN is a tricky market. The reason is that these guys grow so fast to such ENORMOUS sizes. (Mine went from 3" to 2 feet in about 15 months....) They will get well over 3 feet and are difficult to house and feed because of this. As a result, these fish are often found for free at larger sizes since people are desperate to find them a good home. As a result, the fish in general, do not gain value with their size. However, at 14" they do still sell. If you are in the right market in the right economy, the big guys can be sold, and the biggest guys might bring in some decent money. In general however, these fish are normally bought at small sizes and then are up for sale as they outgrow tanks, eat tankmates, and eat you out of house and home.
That said, I LOVE mine, and think making sure I buy a house that can accommodate the kind of setup he needs is great. They have great personalities and are super friendly. Just know you have a monster on your hands that you will be able to watch grow daily.