Welcome To Bike Forums, PapaGaNoosh!
First of all, when you say, "rides smoothly", I'm assuming that you have ridden it personally and are not going by what you've been told by the seller or a second party. I say that because, the most important aspect about a bicycle purchase of any kind, is the fit. That is to say, the comfort level involved in actually riding the bicycle. If you've already ridden the Titan, it feels good, and does not have any rust or weld issues, then I'd say yes indeed, buy it!
However, I think that before you actually shell out the cash, you should bring someone with you who "knows bikes", who might give you a second opinion. Bring $240 but offer $200, for your first offer. Use your skills to bargain down.
* That Titan is definitely worth the money *
Good Luck!
PS.
Look for a bicycle co-op in your area. If there is one in your area, join it, so that you can learn how to both maintain and repair your bicycle. A co-op will teach you bicycle mechanics.