What should I be looking for when buying a used bike?

Would something like this be a good deal:

https://www.gumtree.com/p/bicycles/-mens-gents-adults-raleigh-26-inch-wheels-21-inch-frame-18-speed-bike-bicycle/1504333822

Also what would be some good brands? For mostly just cycling around and go to a cafe or something etc Budget would be less than £200 so what are some good recs? I’ve been told it would be better to go used at this range?