It depends. (Doncha hate answers that start that way!)
If you plan to reproduce Caterpiller D-10 parts, no. If you want to make small parts or maybe build models, it could be. From the pictures, there are no obvious signs of abuse or damage but we can't really judge how much wear is on the machine from this distance. How are the lead, cross-feed and compound screws and their associated nuts? Any stripped teeth in the back gears?
The $750 asking price seems high to me. No 4 jaw chuck? No steady rest or follow rest? Apparently minimal tooling included? Toolholder seems to be limited to a single tool at a time? Drill chuck or live centre for the tailstock? Is the bench even included? All this stuff adds up to real money pretty quickly. No matter what, it requires changing gears to change the feed rate as well as for threading. Some people find that tests their patience to the limit.
HTH
Craig in Oakville