It's been years since I last rented a game. I don't even know any place that does that anymore, actually. When buying a game I often read a lot about it (if it's a new series, or just a game that looks interesting) e.g. the previews, reviews and stuff like that. If it's a game from a series that I really like e.g. Final Fantasy or Tekken I just buy the game because I know I'll like it.