Answer:
Some benefits are that you can then learn what seems to be true. If multiple sources say the same things in some way, it's probably true. Also, some sources may contain more and/or clearer information than others. Some may include quotes others cannot provide, have pictures, and maybe even videos. The more sources you have, the more (accurate) information you can get.
Reference: the action of alluding or mentioning something; source; things that you have used for an assignment
It's been a while since I've read the book and I don't really a lot of the context, so just from this passage I would say it says he notices nice houses and other people's wealth and maybe envies them a little bit. (although you don't get that explicitly from this passage.)
