Before getting anything this size, you should really get a chance of looking at it and more importantly "feeling" it meaning physically moving it around. 12" is huge, and meades are super heavy. If you don't know what you're running into I suggest you wait a bit more until you get to try one.
Also, I suggest you take time and don't rush a 6000-7000 bucks decision, but that's your call of course
And most second hand scopes would - of course - be great.