He can be trained, but he won't be able to reach his full potential. He's already 19.
What are you talking about.. in my opinion the 7'0 guy has a lot more going for him than the $3k 'future SF'.... you have to have tons of patience to create any kind of meaningful player out of the base stats he has..
He might be the best chance yet of raising some cash and I would then try and find your C a mate and train both of them. The inside skills shoot up and will help to keep you more competitive as well.
Note to the original poster. Do check the source and quality of the information you receive. Im not saying I am right but you are on could be on the verge of wasting a lot of time and energy trying to polish up the first guy you showed us.
The perennial allstar Centre and 1 other guy like him are going to be easiest to slot into your team, train single position at C on ID/IS... add some Rebounding then once they are competitive it is for you to decide if you wish to give them some addons such as more passing or JS.
Good luck!