As Charlie rightly points out, a Predicta is not the easiest set to work on. This article gives you some idea what's involved.
http://antiqueradio.org/philc12.htm
Every TV is different, but even if this Predicta currently works after a fashion, I wouldn't expect that you can just take it home, plug it in, and watch it indefinitely. So factor some restoration work (or expense) into your plans.
Phil