Jonny can't be a broker. No one in any state could pass the test and ask a question like this. If Jonny just filled out the Trulia ID thinking it would be misleading or funny he's already on the wrong foot in buying a property.
Seriously though, what "things" or "info" should everyone look for when buying a home? There isn't enough room in this space to answer the question.
Jonny has identified Potrero Hill as a neighborhood and thats a start. Can he afford the area? Does he want multi-family, single-family, condo, etc? What are his goals?
The first thing Jonny needs is a licensed real estate agent or Realtor ( there is a difference Jonny). There is a difference between a licensed agent and broker also. With good representation Jonny will have myriad conversations and learn what to look for, how to narrow down the search, the fact that the entire process is made up of choices that he will have to make, what all the information that he is required to read, understand and sign-off on means, what the market conditions are in the general and specific area is, how to fashion an initial offer, how to arrange inspections specific to the property he is buying, how to understand the infomration presented ini the reports, how to negotiate the terms and price of the property . . . Get the picture Jonny? Find representation and don't misrepresnt yourself in the process it will only come back and bite you, no one else.