Does 75 dollars for this crested seem like a reasonable price?

https://mywebspace.wisc.edu/zcpfiffner/cg.jpg

All I know about it is that it's male, it's roughly 6-7 months old, and it was bought as an f-2 juvie (does anyone know what this means?).

I've met the person that's selling it and she seems very trustworthy and knowledgeable...another perk is that she lives close by so I wouldn't have to pay for shipping.

My only other thought is that if I only purchase one now, but am interested in purchasing another down the road, will they have a hard time acclimating to each other and living with each other?

Thanks for your help
-Zach